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omr-ws-bb0421f7b7107e4fab5d4d4871c1ec48cf55e6076f05ff87fe27d5f88a06b163
Two players take turns removing either one coin or two touching coins from a circle of 13 coins. The player who takes the last coin wins. Formulate a strategy that will ensure a victory for the second player.
[ "Ensure symmetry by picking 2 coins opposite if the first player picks 1, or respond symmetrically if the first player picks 2." ]
[ "Two players take turns removing either one coin or two touching coins from a circle of 13 coins. The player who takes the last coin wins. Formulate a strategy that will ensure a victory for the second player." ]
[ "aops_c4_high_school_math", "c4_high_school_math" ]
[ "cot", "tir" ]
{ "cot": 15, "tir": 6 }
21
0
0
omr-ws-329526f5294f3cbc9f994b89d42693c1b48b3f9f0e35af7f5af45e4f9f3074c6
Two players take turns rolling a die, with the first player going first. The game ends when a player rolls a 1, and that player wins. What is the probability that the player who goes first wins the game?
[ "\\(\\frac{6}{11}\\)" ]
[ "Two players take turns rolling a die, with the first player going first. The game ends when a player rolls a 1, and that player wins. What is the probability that the player who goes first wins the game?" ]
[ "aops_c7_college_math" ]
[ "cot", "tir" ]
{ "cot": 16, "tir": 30 }
46
0
0
omr-ws-4ee6d44cbbe544a9c3b40e08fa9c182f1b63ca3af89f64496985b661b71c2110
Two players take turns saying a number between 1 and 10 inclusive, with player 1 going first. The cumulative sum of the numbers said is kept track of. The person who says the number that makes the sum reach or exceed 50 wins. If a player cannot say a number such that its sum with the last number said equals 11, which p...
[ "1" ]
[ "Two players take turns saying a number between 1 and 10 inclusive, with player 1 going first. The cumulative sum of the numbers said is kept track of. The person who says the number that makes the sum reach or exceed 50 wins. If a player cannot say a number such that its sum with the last number said equals 11, wh...
[ "aops_c4_high_school_math" ]
[ "cot", "genselect" ]
{ "cot": 15, "genselect": 8 }
23
0
0
omr-ws-37e730e5c1c9ad520866a63519476e8f9e363893d5163ed1cbfeafbdd3bee471
Two players take turns saying a number from the set {1, 2, 4}, with player 1 going first. The cumulative sum of the numbers said is kept track of. The person who says the number that makes the sum reach or exceed 50 wins. Which player has the winning strategy?
[ "Second player" ]
[ "Two players take turns saying a number from the set {1, 2, 4}, with player 1 going first. The cumulative sum of the numbers said is kept track of. The person who says the number that makes the sum reach or exceed 50 wins. Which player has the winning strategy?" ]
[ "aops_c4_high_school_math" ]
[ "cot", "tir" ]
{ "cot": 16, "tir": 18 }
34
0
0
omr-ws-6a8daf849f81f5428dc7b80aa3d7ab1d2353b3121bc2e5de20bb0e347857307b
Two players take turns splitting a 4x6x9 rectangular parallelepiped, made up of 216 unit cubes, into two smaller rectangular parallelepipeds using a plane. The player who makes the last split wins. Which player has the winning strategy?
[ "The first player has the winning strategy." ]
[ "Two players take turns splitting a 4x6x9 rectangular parallelepiped, made up of 216 unit cubes, into two smaller rectangular parallelepipeds using a plane. The player who makes the last split wins. Which player has the winning strategy?" ]
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect", "tir" ]
{ "cot": 10, "genselect": 4, "tir": 27 }
41
0
0
omr-ws-d462c1ba272b18aee0922f2fc9492ef4af6b444b7f3ddb867b383c3ae879cd7a
Two players take turns subtracting 1 from one of the coefficients of the quadratic function \( f(x) = x^2 + 25x + 425 \). The player who makes the function have real roots wins. Determine which player has a winning strategy.
[ "The second player has a winning strategy." ]
[ "Two players take turns subtracting 1 from one of the coefficients of the quadratic function \\( f(x) = x^2 + 25x + 425 \\). The player who makes the function have real roots wins. Determine which player has a winning strategy." ]
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect", "tir" ]
{ "cot": 13, "genselect": 6, "tir": 14 }
33
0
0
omr-ws-2e7d4f0e9e121b15e47301cf9e14ac067b990f6f98c80cd381a91188f4c7c894
Two players take turns taking 1 or 2 stones from one pile, randomly selected from a given set of 3 ordered piles, initially containing 100, 200, and 300 stones, in order from left to right. It is forbidden to make a move that results in the left pile having more stones than the right pile. If after a player's move, no ...
[ "\\text{Second player}" ]
[ "Two players take turns taking 1 or 2 stones from one pile, randomly selected from a given set of 3 ordered piles, initially containing 100, 200, and 300 stones, in order from left to right. It is forbidden to make a move that results in the left pile having more stones than the right pile. If after a player's move...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect" ]
{ "cot": 12, "genselect": 6 }
18
0
0
omr-ws-41a4ecb9619bfe3019c52f1c0c6de25a70f4bdcbe21ef3396cc3112842ed2aac
Two players take turns taking 1, 2, or 3 stones from a given set of 3 piles, initially containing 11, 22, and 33 stones. If after a player's move, any two piles have the same number of stones, that player wins. Who will win with the right game of both players?
[ "\\text{Second player}" ]
[ "Two players take turns taking 1, 2, or 3 stones from a given set of 3 piles, initially containing 11, 22, and 33 stones. If after a player's move, any two piles have the same number of stones, that player wins. Who will win with the right game of both players?" ]
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect" ]
{ "cot": 12, "genselect": 8 }
20
0
0
omr-ws-7ff20053c619938d8703deed5b8ae4c388c9789eeccab90cde71b9e73db1582c
Two players take turns taking stones from a pile of 10 million stones. On every move, a player must take \( p^n \) stones, where \( p \) is any prime number and \( n \) is any non-negative integer (chosen by the player making the move). The person who takes the last stone wins. Who has a winning strategy and what is it...
[ "First player has a winning strategy." ]
[ "Two players take turns taking stones from a pile of 10 million stones. On every move, a player must take \\( p^n \\) stones, where \\( p \\) is any prime number and \\( n \\) is any non-negative integer (chosen by the player making the move). The person who takes the last stone wins. Who has a winning strategy and...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "tir" ]
{ "cot": 16, "tir": 28 }
44
0
0
omr-ws-b51dd530b1f15f3e8c5acafa0026f51368494ea673b38322c6f2b4c05e6b9092
Two players take turns writing down all proper non-decreasing fractions with denominators from $1$ to $1999$ and placing a "$+$" sign before each fraction. After all such fractions are written out, their sum is found. If this sum is an integer, the player who made the last entry wins; otherwise, the opponent wins. Who ...
[ "The player who makes the last entry can secure a win." ]
[ "Two players take turns writing down all proper non-decreasing fractions with denominators from $1$ to $1999$ and placing a \"$+$\" sign before each fraction. After all such fractions are written out, their sum is found. If this sum is an integer, the player who made the last entry wins; otherwise, the opponent win...
[ "aops_c4_high_school_math", "c4_high_school_math" ]
[ "cot", "genselect", "tir" ]
{ "cot": 12, "genselect": 4, "tir": 30 }
46
0
0
omr-ws-1d85f0719430d85189a4839926118f088ee53b7f23fb7ad1e004bee4deb10d68
Two players take turns writing natural numbers on a board, with the rules that numbers cannot be greater than $p$ and cannot be divisors of previously written numbers. The player who cannot make a move loses. Determine which player has a winning strategy for $p = 10$ and describe this strategy.
[ "The first player has a winning strategy." ]
[ "Two players take turns writing natural numbers on a board, with the rules that numbers cannot be greater than $p$ and cannot be divisors of previously written numbers. The player who cannot make a move loses. Determine which player has a winning strategy for $p = 10$ and describe this strategy." ]
[ "aops_c4_high_school_math" ]
[ "cot", "genselect", "tir" ]
{ "cot": 14, "genselect": 6, "tir": 17 }
37
0
0
omr-ws-45c31d281b98073da5689bd29239758f3b35b718d545c9ea006dfc860c6ee630
Two players take turns writing on a board starting with the number "0". The first player writes a "+" or "-" sign, and the second player writes a natural number from 1 to 1993, each number used exactly once. After 1993 moves by each player, the second player receives a prize equal to the absolute value of the arithmeti...
[ "993010" ]
[ "Two players take turns writing on a board starting with the number \"0\". The first player writes a \"+\" or \"-\" sign, and the second player writes a natural number from 1 to 1993, each number used exactly once. After 1993 moves by each player, the second player receives a prize equal to the absolute value of th...
[ "aops_c4_high_school_math" ]
[ "additional_problems" ]
{ "additional_problems": 1 }
1
0
0
omr-ws-f402209142d4b56e1d704d0dced37dbcbce296e9e9abfd09efc3880d8a028e4e
Two players write integers on a blackboard according to the following rules: - The first player writes $1$. - At each subsequent turn, a player must write either $a+1$ or $2a$, where $a$ is any number already written on the blackboard and $2a \leq 1000$. - No number can be written more than once. - The player who write...
[ "\\text{Second player}" ]
[ "Two players write integers on a blackboard according to the following rules:\n- The first player writes $1$.\n- At each subsequent turn, a player must write either $a+1$ or $2a$, where $a$ is any number already written on the blackboard and $2a \\leq 1000$.\n- No number can be written more than once.\n- The player...
[ "aops_c6_high_school_olympiads" ]
[ "genselect" ]
{ "genselect": 4 }
4
0
0
omr-ws-9a0ee6424439dff8a4f3915be24d1ce4d91450e2c2061765bcde96670179495c
Two players write integers on a blackboard according to the following rules: - The first player writes $1$. - At each subsequent turn, the player writes either $a+1$ or $2a$, where $a$ is any number already written on the blackboard and $2a \leq 1000$. - No number can be written more than once. - The player who writes ...
[ "The first player loses." ]
[ "Two players write integers on a blackboard according to the following rules:\n- The first player writes $1$.\n- At each subsequent turn, the player writes either $a+1$ or $2a$, where $a$ is any number already written on the blackboard and $2a \\leq 1000$.\n- No number can be written more than once.\n- The player w...
[ "aops_c6_high_school_olympiads" ]
[ "genselect" ]
{ "genselect": 5 }
5
0
0
omr-ws-6290ee5ade490ca64e2e3c5a1c0e815d0b6454ff67e5eb18d9ac6e70e68dfc3f
Two players, $A$ and $B$, alternatively take stones from a pile of $n \geq 2$ stones. $A$ plays first and must take at least one stone and at most $n-1$ stones. Then each player must take at least one stone and at most as many stones as their opponent took in the previous move. The player who takes the last stone wins....
[ "Player $B$ has a winning strategy if $n$ is a power of 2; otherwise, player $A$ has a winning strategy." ]
[ "Two players, $A$ and $B$, alternatively take stones from a pile of $n \\geq 2$ stones. $A$ plays first and must take at least one stone and at most $n-1$ stones. Then each player must take at least one stone and at most as many stones as their opponent took in the previous move. The player who takes the last stone...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "tir" ]
{ "cot": 1, "tir": 26 }
27
0
0
omr-ws-cb605191d94da4658109cddfba14a957d368797ee7b5d6f00221b8e4da78331a
Two players, $A$ and $B$, are playing a game on a plane with 2020 points. They take turns adding segments between these points, with $A$ going first. The rule is that no cycle of length 4 can be formed. The first player who cannot add a segment loses. Calculate the maximum number of segments that can be added to the pl...
[ "45450" ]
[ "Two players, $A$ and $B$, are playing a game on a plane with 2020 points. They take turns adding segments between these points, with $A$ going first. The rule is that no cycle of length 4 can be formed. The first player who cannot add a segment loses. Calculate the maximum number of segments that can be added to t...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect" ]
{ "cot": 3, "genselect": 5 }
8
0
0
omr-ws-1395f1cc1fd39212c2259ac7499ae3d8f373624a590f2a6567b6814a1c968f40
Two players, $A$ and $B$, consecutively make moves on a blackboard with natural numbers $1, 2, \ldots, 500$. Each move consists of choosing two numbers $n$ and $2n$ and erasing them. If a player cannot perform a valid move, he loses. Which player can guarantee a win?
[ "A" ]
[ "Two players, $A$ and $B$, consecutively make moves on a blackboard with natural numbers $1, 2, \\ldots, 500$. Each move consists of choosing two numbers $n$ and $2n$ and erasing them. If a player cannot perform a valid move, he loses. Which player can guarantee a win?" ]
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect" ]
{ "cot": 7, "genselect": 8 }
15
0
0
omr-ws-f6f5dbd95e25b88f37b09735b10b2b6970cf5ea83f5ac247d41242052cc3e6e1
Two players, $A$ and $B$, each have two piles of $n$ coins, where $n$ is a positive integer with at least 2 distinct prime factors and is a perfect square of a composite number. Each player can remove or add a number of coins from/to one of their piles, which is a divisor of the number of coins already in that pile (ex...
[ "Yes" ]
[ "Two players, $A$ and $B$, each have two piles of $n$ coins, where $n$ is a positive integer with at least 2 distinct prime factors and is a perfect square of a composite number. Each player can remove or add a number of coins from/to one of their piles, which is a divisor of the number of coins already in that pil...
[ "aops_c6_high_school_olympiads" ]
[ "cot" ]
{ "cot": 8 }
8
0
0
omr-ws-65d4b36069055e1adb250f5903b9c211ec32a61ef0e3bbb95097d4ef9cd6abe3
Two players, $A$ and $B$, play a game on a rhombus-shaped board of side $n$ and angles of $60^{\circ}$ and $120^{\circ}$, divided into $2n^2$ equilateral triangles. The tokens are initially placed in cells containing opposite $60^{\circ}$ corners. Players take turns moving their token to a neighboring cell (sharing a s...
[ "A has a winning strategy." ]
[ "Two players, $A$ and $B$, play a game on a rhombus-shaped board of side $n$ and angles of $60^{\\circ}$ and $120^{\\circ}$, divided into $2n^2$ equilateral triangles. The tokens are initially placed in cells containing opposite $60^{\\circ}$ corners. Players take turns moving their token to a neighboring cell (sha...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect", "tir" ]
{ "cot": 13, "genselect": 7, "tir": 4 }
24
0
0
omr-ws-02fcf97384c85d47a2534a54566fb1e52e40fbf4bdf317c536d7a85bf07142c4
Two players, $A$ and $B$, play a game on an $n \times n$ board. Each player has a rook on opposite corners. In a move, a player can move their rook horizontally or vertically through any number of squares, provided all squares passed through are previously unvisited. After the move, all passed squares are considered vi...
[ "B" ]
[ "Two players, $A$ and $B$, play a game on an $n \\times n$ board. Each player has a rook on opposite corners. In a move, a player can move their rook horizontally or vertically through any number of squares, provided all squares passed through are previously unvisited. After the move, all passed squares are conside...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect" ]
{ "cot": 10, "genselect": 4 }
14
0
0
omr-ws-786bd092fc334509ca96d00d47468ac0512e48d9b56ea5dd8831d41bd6bc15e6
Two players, $A$ and $B$, play a game on an $n \times n$ empty square table. $A$ starts the game and they take turns. On each move, a player places one marble on a cell if all neighboring cells are empty. Two cells are neighbors if they share a vertex. The player who cannot make a move loses. Determine the winner for e...
[ "A" ]
[ "Two players, $A$ and $B$, play a game on an $n \\times n$ empty square table. $A$ starts the game and they take turns. On each move, a player places one marble on a cell if all neighboring cells are empty. Two cells are neighbors if they share a vertex. The player who cannot make a move loses. Determine the winner...
[ "aops_c6_high_school_olympiads" ]
[ "cot" ]
{ "cot": 7 }
7
0
0
omr-ws-4cf10a272d7ef611c60dc4593eb991dff9a4c33b6cf4a8bd43c5b4022d26f78f
Two players, $A$ and $B$, play a game starting with a positive integer $n$. On each turn, a player can subtract one of the following from $n$: - $1$ - the number of digits of $n$ - the sum of the digits of $n$ The player who reduces $n$ to $0$ wins. If $A$ goes first, determine who will be the winner given the initial ...
[ "B" ]
[ "Two players, $A$ and $B$, play a game starting with a positive integer $n$. On each turn, a player can subtract one of the following from $n$: \n- $1$\n- the number of digits of $n$\n- the sum of the digits of $n$\n\nThe player who reduces $n$ to $0$ wins. If $A$ goes first, determine who will be the winner given ...
[ "aops_c6_high_school_olympiads" ]
[ "cot" ]
{ "cot": 8 }
8
0
0
omr-ws-b48f0ce1271d0daac1c1b7754530eccd4ab4301f640ec627fecf3a0a10f98c58
Two players, $A$ and $B$, play a game starting with a positive integer $n_0$ on a blackboard. On each turn, a player deletes the current number $n_k$ and writes either $n_k-1$ or $\left\lfloor \frac{n_k}{3} \right\rfloor$. The game ends when the number becomes 0, and the player who writes 0 wins. Determine which player...
[ "B" ]
[ "Two players, $A$ and $B$, play a game starting with a positive integer $n_0$ on a blackboard. On each turn, a player deletes the current number $n_k$ and writes either $n_k-1$ or $\\left\\lfloor \\frac{n_k}{3} \\right\\rfloor$. The game ends when the number becomes 0, and the player who writes 0 wins. Determine wh...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "tir" ]
{ "cot": 16, "tir": 19 }
35
0
0
omr-ws-b920c9c6a10b87b23bd9df7da75ee5371abde6bf38e34dc73d0a837480a2c262
Two players, $A$ and $B$, play a game starting with a positive integer $n_0$ on a blackboard. On each turn, a player deletes the current number $n_k$ and writes either $n_k-1$ or $\left\lfloor \frac{n_k}{3} \right\rfloor$. The game ends when the number becomes 0, and the player who writes 0 wins. Determine which player...
[ "B" ]
[ "Two players, $A$ and $B$, play a game starting with a positive integer $n_0$ on a blackboard. On each turn, a player deletes the current number $n_k$ and writes either $n_k-1$ or $\\left\\lfloor \\frac{n_k}{3} \\right\\rfloor$. The game ends when the number becomes 0, and the player who writes 0 wins. Determine wh...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect", "tir" ]
{ "cot": 47, "genselect": 5, "tir": 17 }
69
0
0
omr-ws-8c4941c44789058a3c875fba4e3e624815a79aa61aa8ed417a231351d1f800ab
Two players, $A$ and $B$, play a game starting with a positive integer $n_0$ on a blackboard. On each turn, a player deletes the current number $n_k$ and writes either $n_k-1$ or $\left\lfloor \frac{n_k}{3} \right\rfloor$. The game ends when the number becomes 0, and the player who writes 0 wins. Determine which player...
[ "A" ]
[ "Two players, $A$ and $B$, play a game starting with a positive integer $n_0$ on a blackboard. On each turn, a player deletes the current number $n_k$ and writes either $n_k-1$ or $\\left\\lfloor \\frac{n_k}{3} \\right\\rfloor$. The game ends when the number becomes 0, and the player who writes 0 wins. Determine wh...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect", "tir" ]
{ "cot": 15, "genselect": 8, "tir": 13 }
36
0
0
omr-ws-18456032619bd00591aed862553bdd17cf88be261d9ce9b0178913a183eb35bf
Two players, $A$ and $B$, play a game starting with the number $1234567890$ on the blackboard. In each move, a player erases the current number $m$, subtracts from $m$ any positive integer not exceeding the sum of the digits of $m$, and writes the result. The first player to reduce the number to $0$ wins. Determine whi...
[ "Player \\(A\\) has the winning strategy.", "\\( A \\) has the winning strategy." ]
[ "Two players, $A$ and $B$, play a game starting with the number $1234567890$ on the blackboard. In each move, a player erases the current number $m$, subtracts from $m$ any positive integer not exceeding the sum of the digits of $m$, and writes the result. The first player to reduce the number to $0$ wins. Determin...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect", "tir" ]
{ "cot": 7, "genselect": 1, "tir": 3 }
11
0
0
omr-ws-b35b20500b3d7ac88f696ab65313df984c1d36555c2efc49af82b1ed0df75977
Two players, $A$ and $B$, play a game starting with the number $2024$ on the board. They take turns reducing the number by a natural number that does not exceed the number of the move (with the first move $A$ must reduce by $1$, $B$ by $1$ or $2$, then $A$ by $1$, $2$, or $3$, and so on). The player who first reduces t...
[ "B has the winning strategy." ]
[ "Two players, $A$ and $B$, play a game starting with the number $2024$ on the board. They take turns reducing the number by a natural number that does not exceed the number of the move (with the first move $A$ must reduce by $1$, $B$ by $1$ or $2$, then $A$ by $1$, $2$, or $3$, and so on). The player who first redu...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect", "tir" ]
{ "cot": 13, "genselect": 7, "tir": 10 }
30
0
0
omr-ws-2b8ca93cb413d4139e4c21ca3a24de0e4c08ec1291911add6e516eede12aee92
Two players, $A$ and $B$, play a game where $A$ chooses a positive integer $k$ and $B$ chooses a positive integer $n$. They alternately mark points in the plane until both have marked $n$ points. $B$ wins if the number of lines passing through at least two marked points is divisible by $k$. Otherwise, $A$ wins. Which p...
[ "B" ]
[ "Two players, $A$ and $B$, play a game where $A$ chooses a positive integer $k$ and $B$ chooses a positive integer $n$. They alternately mark points in the plane until both have marked $n$ points. $B$ wins if the number of lines passing through at least two marked points is divisible by $k$. Otherwise, $A$ wins. Wh...
[ "aops_c7_college_math" ]
[ "cot", "genselect" ]
{ "cot": 10, "genselect": 4 }
14
0
0
omr-ws-0f38473b93398049e8741dfaa15335e48f3838c408212c71e8d00f52e2e0afb3
Two players, $A$ and $B$, play a game with a pile of $N$ stones where $2 \leq N$. The players alternate turns, with $A$ going first. On the first turn, $A$ must remove at least $1$ and at most $N-1$ stones. If a player removes $k$ stones on their turn, the other player must remove at least $1$ and at most $2k-1$ stones...
[ "\\( A \\) wins if \\( N \\) is not a power of 2, and \\( B \\) wins if \\( N \\) is a power of 2." ]
[ "Two players, $A$ and $B$, play a game with a pile of $N$ stones where $2 \\leq N$. The players alternate turns, with $A$ going first. On the first turn, $A$ must remove at least $1$ and at most $N-1$ stones. If a player removes $k$ stones on their turn, the other player must remove at least $1$ and at most $2k-1$ ...
[ "aops_c6_high_school_olympiads" ]
[ "tir" ]
{ "tir": 24 }
24
0
0
omr-ws-6b137f2b5c02d218828fc4e4154b4f0125c3219771847c60dd8ae45af8b31c2b
Two players, $A$ and $B$, play a game with a positive integer $n$. At each turn, starting with player $A$, a player chooses 2 out of $n$ sets and removes the same number of elements from both sets, where each removed element appears in both sets and in those 2 sets only, and the number of elements removed is greater th...
[ "n \\equiv 0 \\text{ or } 1 \\pmod{4}" ]
[ "Two players, $A$ and $B$, play a game with a positive integer $n$. At each turn, starting with player $A$, a player chooses 2 out of $n$ sets and removes the same number of elements from both sets, where each removed element appears in both sets and in those 2 sets only, and the number of elements removed is great...
[ "aops_c6_high_school_olympiads" ]
[ "cot" ]
{ "cot": 15 }
15
0
0
omr-ws-349d7d0ec85cf891168e7ece2165f25abd326695b266052eb8e8b8c30e8f0b5f
Two players, $A$ and $B$, play a game with the expression $\pm \Box \pm \Box \pm \Box \pm \Box \pm \Box \pm \Box$. Player $A$ moves first by replacing one of the $\Box$ with an arbitrary natural number. After all $\Box$ are replaced, $A$ replaces each $\pm$ with a plus or a minus. $A$ wins if the resulting expression's...
[ "A" ]
[ "Two players, $A$ and $B$, play a game with the expression $\\pm \\Box \\pm \\Box \\pm \\Box \\pm \\Box \\pm \\Box \\pm \\Box$. Player $A$ moves first by replacing one of the $\\Box$ with an arbitrary natural number. After all $\\Box$ are replaced, $A$ replaces each $\\pm$ with a plus or a minus. $A$ wins if the re...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect" ]
{ "cot": 15, "genselect": 8 }
23
0
0
omr-ws-a60f5e377958856b6bf0b4ce66719627d1fe204af79565d4eac325d00eceed5e
Two players, $A$ and $B$, play a game with the expression \[ \pm \Box \pm \Box \pm \Box \pm \Box \pm \Box \pm \Box. \] Player $A$ takes the first turn, and in each turn, the player replaces a symbol $\Box$ with a positive integer. After all $\Box$ symbols are replaced, player $A$ replaces each $\pm$ with either $+$ or ...
[ "A" ]
[ "Two players, $A$ and $B$, play a game with the expression\n\\[ \\pm \\Box \\pm \\Box \\pm \\Box \\pm \\Box \\pm \\Box \\pm \\Box. \\]\nPlayer $A$ takes the first turn, and in each turn, the player replaces a symbol $\\Box$ with a positive integer. After all $\\Box$ symbols are replaced, player $A$ replaces each $\...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect" ]
{ "cot": 13, "genselect": 7 }
20
0
0
omr-ws-73125a770925a5ccabbdae99c2d7a772194f8a9a6b503314ca18aded3e0b6183
Two players, $A$ and $B$, play a game with the following rules: - $B$ starts by writing a positive integer $N$ on the blackboard. - Players alternate turns, with $A$ taking the first turn. - On each turn, a player can either "mirror" or "mimic" (if the previous player mirrored): - To "mirror," the player writes a posit...
[ "A \\text{ wins if } N \\text{ is prime; otherwise, } B \\text{ wins}" ]
[ "Two players, $A$ and $B$, play a game with the following rules:\n- $B$ starts by writing a positive integer $N$ on the blackboard.\n- Players alternate turns, with $A$ taking the first turn.\n- On each turn, a player can either \"mirror\" or \"mimic\" (if the previous player mirrored):\n - To \"mirror,\" the play...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect" ]
{ "cot": 9, "genselect": 2 }
11
0
0
omr-ws-f3a3d76287e614648fb188a0657eb36b6ff76e2feb61e81ca7d145fdd83df6d7
Two players, $A$ and $B$, play a game with the following rules: - The set $S$ contains all perfect squares: $S = \{1^2, 2^2, 3^2, \ldots\}$. - Initially, $M = 0$. - Players take turns choosing an element $X$ from $S$ such that $M + X \leq 2013$. - The chosen element $X$ is added to $M$, updating $M$ to $M + X$. - The p...
[ "B" ]
[ "Two players, $A$ and $B$, play a game with the following rules:\n- The set $S$ contains all perfect squares: $S = \\{1^2, 2^2, 3^2, \\ldots\\}$.\n- Initially, $M = 0$.\n- Players take turns choosing an element $X$ from $S$ such that $M + X \\leq 2013$.\n- The chosen element $X$ is added to $M$, updating $M$ to $M ...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect" ]
{ "cot": 11, "genselect": 5 }
16
0
0
omr-ws-c01d07d044702f1387dab97c6ddf8483e425afead39da68b320e6fc3c9db6e93
Two players, $A$ and $B$, play a game with the polynomial $x^{30} + *x^{29} + \ldots + *x + 8 = 0$. Player $A$ starts by replacing all asterisks with the natural numbers from $1$ to $30$ (each used exactly once). Player $B$ then replaces some of the $+$ signs with $-$ signs. Player $A$ aims to create a polynomial with ...
[ "B" ]
[ "Two players, $A$ and $B$, play a game with the polynomial $x^{30} + *x^{29} + \\ldots + *x + 8 = 0$. Player $A$ starts by replacing all asterisks with the natural numbers from $1$ to $30$ (each used exactly once). Player $B$ then replaces some of the $+$ signs with $-$ signs. Player $A$ aims to create a polynomial...
[ "aops_c6_high_school_olympiads" ]
[ "cot" ]
{ "cot": 16 }
16
0
0
omr-ws-34a130c4d20d513d53261c2f6a59140f43357b18187b484ce8598a4fbd9303f0
Two players, $A$ and $B$, play a game with the positive divisors of a positive integer $N$ written on a blackboard. In the first move, player $A$ erases $N$. If the last erased number is $d$, the next player must erase either a divisor of $d$ or a multiple of $d$. The player who cannot make a move loses. Determine all ...
[ "\\( N \\) must be a perfect square." ]
[ "Two players, $A$ and $B$, play a game with the positive divisors of a positive integer $N$ written on a blackboard. In the first move, player $A$ erases $N$. If the last erased number is $d$, the next player must erase either a divisor of $d$ or a multiple of $d$. The player who cannot make a move loses. Determine...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect", "tir" ]
{ "cot": 10, "genselect": 8, "tir": 2 }
20
0
0
omr-ws-c6f01b4e41018c5838270e183c444bacd5c167e5bd84b31520bbe125156d8698
Two players, $A$ and $B$, play a series of games where the probability of $A$ winning a game is $\frac{1}{3}$ and the probability of $B$ winning a game is $\frac{2}{3}$. The series is won by $A$ if $A$ wins 2 consecutive games, and by $B$ if $B$ wins 4 consecutive games. Find the probability that $B$ wins the series.
[ "\\(\\frac{64}{129}\\)" ]
[ "Two players, $A$ and $B$, play a series of games where the probability of $A$ winning a game is $\\frac{1}{3}$ and the probability of $B$ winning a game is $\\frac{2}{3}$. The series is won by $A$ if $A$ wins 2 consecutive games, and by $B$ if $B$ wins 4 consecutive games. Find the probability that $B$ wins the se...
[ "aops_c7_college_math" ]
[ "cot", "tir" ]
{ "cot": 16, "tir": 8 }
24
0
0
omr-ws-3151b5da32177c68e76b60820231f30a289f803627f7a2bfd289d6822425dd3c
Two players, $A$ and $B$, play alternately, starting with $A$. There are 2009 boxes numbered from 1 to 2009, with 2009 stones in box 2 and the others empty. A move consists in selecting a non-empty box $i$, taking one or more stones from that box and putting them in box $i + 1$. If $i = 2009$, the selected stones are e...
[ "Player $B$ has a winning strategy." ]
[ "Two players, $A$ and $B$, play alternately, starting with $A$. There are 2009 boxes numbered from 1 to 2009, with 2009 stones in box 2 and the others empty. A move consists in selecting a non-empty box $i$, taking one or more stones from that box and putting them in box $i + 1$. If $i = 2009$, the selected stones ...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect", "tir" ]
{ "cot": 26, "genselect": 5, "tir": 14 }
45
0
0
omr-ws-cd7e55fafcef34a7be02136e7f23e6ce812f1be8017ad5df26e37453e3168d4f
Two players, $A$ and $B$, play alternately, starting with $A$. There are 2009 boxes numbered from 1 to 2009, with exactly one stone in each box. A move consists in selecting a non-empty box $i$, taking one or more stones from that box and putting them in box $i + 1$. If $i = 2009$, the selected stones are eliminated. T...
[ "Player \\( A \\) has a winning strategy." ]
[ "Two players, $A$ and $B$, play alternately, starting with $A$. There are 2009 boxes numbered from 1 to 2009, with exactly one stone in each box. A move consists in selecting a non-empty box $i$, taking one or more stones from that box and putting them in box $i + 1$. If $i = 2009$, the selected stones are eliminat...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect", "tir" ]
{ "cot": 13, "genselect": 5, "tir": 12 }
30
0
0
omr-ws-c099f5e31726bc0e8ddb9ecf1c7d7d5bbd9df7cbd0583145475426fe45a921d4
Two players, $A$ and $B$, take turns drawing pieces of paper with numbers $1$ through $9$ written on them. The winner is the first player to have three pieces of paper whose numbers sum to $15$. If $A$ goes first, determine who has a winning strategy.
[ "A" ]
[ "Two players, $A$ and $B$, take turns drawing pieces of paper with numbers $1$ through $9$ written on them. The winner is the first player to have three pieces of paper whose numbers sum to $15$. If $A$ goes first, determine who has a winning strategy." ]
[ "aops_c6_high_school_olympiads" ]
[ "cot" ]
{ "cot": 16 }
16
0
0
omr-ws-180eff04d1a143add3ee3977bb454592ff8f0489ab0df31cb105674d67960ef5
Two players, $A$ and $B$, take turns picking up cards numbered from $1$ to $2002$. The player who ends up with the sum of their cards having a larger last digit than their opponent wins. $A$ goes first. Who has a winning strategy, and what is the strategy to win?
[ "Player \\( A \\) has a winning strategy." ]
[ "Two players, $A$ and $B$, take turns picking up cards numbered from $1$ to $2002$. The player who ends up with the sum of their cards having a larger last digit than their opponent wins. $A$ goes first. Who has a winning strategy, and what is the strategy to win?" ]
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect", "tir" ]
{ "cot": 10, "genselect": 6, "tir": 11 }
27
0
0
omr-ws-07149165e929a9ecb7d84b78ab04f0e80686f1b81d62a50794a34724f0725a36
Two players, $A$ and $B$, take turns saying an integer greater than 1. A number cannot be said if it can be written as the sum of positive multiples of numbers already said. The player who cannot say a number loses. If $A$ starts, who has a winning strategy?
[ "A has a winning strategy." ]
[ "Two players, $A$ and $B$, take turns saying an integer greater than 1. A number cannot be said if it can be written as the sum of positive multiples of numbers already said. The player who cannot say a number loses. If $A$ starts, who has a winning strategy?" ]
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect", "tir" ]
{ "cot": 9, "genselect": 7, "tir": 3 }
19
0
0
omr-ws-549980373d17492d9afcf342399a09d70d558cb21c0411b3f995de88121d935a
Two players, $B$ and $R$, play the following game on an infinite grid of unit squares, all initially colored white. The players take turns starting with $B$. On $B$ 's turn, $B$ selects one white unit square and colors it blue. On $R$ 's turn, $R$ selects two white unit squares and colors them red. The players alternat...
[ "4" ]
[ "Two players, $B$ and $R$, play the following game on an infinite grid of unit squares, all initially colored white. The players take turns starting with $B$. On $B$ 's turn, $B$ selects one white unit square and colors it blue. On $R$ 's turn, $R$ selects two white unit squares and colors them red. The players alt...
[ "MATH_training_set" ]
[ "cot" ]
{ "cot": 16 }
16
0
0
omr-ws-1d3a8e559d17f0dfd1a3674466a9ceccbc4e473d7022813e3f946d3fdf7dc536
Two players, A and B, are playing a game starting with a cubic polynomial. During the game, the players can perform the following operations: 1. Replace the polynomial \( f(x) \) with \( f(nx) \), \( f(x+n) \), or \( f(x) + n \) where \( n \) is a natural number. 2. Change the sign of the coefficient of \( x^2 \) only....
[ "f(x) = ax^3" ]
[ "Two players, A and B, are playing a game starting with a cubic polynomial. During the game, the players can perform the following operations:\n1. Replace the polynomial \\( f(x) \\) with \\( f(nx) \\), \\( f(x+n) \\), or \\( f(x) + n \\) where \\( n \\) is a natural number.\n2. Change the sign of the coefficient o...
[ "aops_c4_high_school_math" ]
[ "cot", "genselect" ]
{ "cot": 5, "genselect": 1 }
6
0
0
omr-ws-f12438d537d91f42378b541c07ba8d6784310b42f9bdc1e18e386c90480f50d9
Two players, A and B, are playing a game starting with a number \( n = p_1^{\alpha_1} p_2^{\alpha_2} \cdots p_k^{\alpha_k} \). The players take turns dividing \( n \) by \( p^k \) where \( k \leq x \) and \( p \in \{p_1, p_2, \ldots, p_k\} \) such that \( p^k \mid n \). The player who reduces \( n \) to 1 wins. Who has...
[ "Player B" ]
[ "Two players, A and B, are playing a game starting with a number \\( n = p_1^{\\alpha_1} p_2^{\\alpha_2} \\cdots p_k^{\\alpha_k} \\). The players take turns dividing \\( n \\) by \\( p^k \\) where \\( k \\leq x \\) and \\( p \\in \\{p_1, p_2, \\ldots, p_k\\} \\) such that \\( p^k \\mid n \\). The player who reduces...
[ "aops_c6_high_school_olympiads" ]
[ "cot" ]
{ "cot": 13 }
13
0
0
omr-ws-d2af834129dda4dd075bc7bd0d60c19c8876b24e1ee121d339f55d6dde759d4d
Two players, A and B, are playing a game with 4 boxes of candies. The first box contains 9 candies, the second contains 18 candies, and the third contains 34 candies. Player B can choose the number of candies in the fourth box. Each player, on their turn, can take any number of candies from exactly one box. The player ...
[ "57" ]
[ "Two players, A and B, are playing a game with 4 boxes of candies. The first box contains 9 candies, the second contains 18 candies, and the third contains 34 candies. Player B can choose the number of candies in the fourth box. Each player, on their turn, can take any number of candies from exactly one box. The pl...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "tir" ]
{ "cot": 16, "tir": 18 }
34
0
0
omr-ws-3eda2a494f721197cface8f699d78e69729b4936f013fff3835c11785b57b8c6
Two players, A and B, are playing a sequence of matches where the first to reach 6 points wins. Each match results in one player winning 1 point and the other losing. The game is interrupted when the score is 4:3 in favor of player A. Assuming both players have approximately equal performance, what should be the ratio ...
[ "1:1" ]
[ "Two players, A and B, are playing a sequence of matches where the first to reach 6 points wins. Each match results in one player winning 1 point and the other losing. The game is interrupted when the score is 4:3 in favor of player A. Assuming both players have approximately equal performance, what should be the r...
[ "aops_c7_college_math" ]
[ "additional_problems" ]
{ "additional_problems": 1 }
1
0
0
omr-ws-93ebb6c35f84570b579e8edea5d9ea2f729ef9c2a5d9524308608fefa052aad8
Two players, A and B, are throwing two fair dice. Player A wins if the sum of the dice is 7, and player B wins if the sum is 6 or 8. Player A goes first. What is the probability that player A will win after n throws?
[ "\\dfrac{18}{43} \\left(1 - \\left(\\dfrac{65}{108}\\right)^{\\lceil n/2 \\rceil}\\right)" ]
[ "Two players, A and B, are throwing two fair dice. Player A wins if the sum of the dice is 7, and player B wins if the sum is 6 or 8. Player A goes first. What is the probability that player A will win after n throws?" ]
[ "aops_c4_high_school_math" ]
[ "cot", "genselect" ]
{ "cot": 10, "genselect": 3 }
13
0
0
omr-ws-6b60593472bb4b55c1c1f4d3a0b35eb7e1c1b4b994af7ab50c8dcf0f5fd8d210
Two players, A and B, play a game on a circle with 99 equally spaced points. On each turn, a player selects an unused number from 1 to 99 and assigns it to one of the points. The player who first completes an arithmetic sequence of three consecutive numbers around the circle wins. Player A goes first. Determine which p...
[ "A" ]
[ "Two players, A and B, play a game on a circle with 99 equally spaced points. On each turn, a player selects an unused number from 1 to 99 and assigns it to one of the points. The player who first completes an arithmetic sequence of three consecutive numbers around the circle wins. Player A goes first. Determine wh...
[ "aops_c6_high_school_olympiads" ]
[ "cot" ]
{ "cot": 16 }
16
0
0
omr-ws-78c344d4e4bc43f097c51cfe9ea00c334dbb708a6eaababed60f772f288bef43
Two players, A and B, play a game on a graph G with vertices labeled $P_1, P_2, \ldots, P_n$. Positive real numbers $x_{i \to j}$ are given for each edge. Player A starts by selecting a vertex, writing 1 on it, and coloring it red. Player B then selects a vertex, writes a number on it, and colors it blue. Players alter...
[ "A" ]
[ "Two players, A and B, play a game on a graph G with vertices labeled $P_1, P_2, \\ldots, P_n$. Positive real numbers $x_{i \\to j}$ are given for each edge. Player A starts by selecting a vertex, writing 1 on it, and coloring it red. Player B then selects a vertex, writes a number on it, and colors it blue. Player...
[ "aops_c6_high_school_olympiads" ]
[ "cot" ]
{ "cot": 16 }
16
0
0
omr-ws-efb084732b69a3c177aba0a5463ede1eb58304fc592c16f6ca949200aba98361
Two players, A and B, play a game on a row of 2018 squares numbered from 0 to 2017. Initially, a coin is placed on square 0. Players take turns moving the coin either 53 squares forward or 2 squares backward, without going beyond the bounds of the row. The player who places the coin on square 2017 wins. Determine which...
[ "A" ]
[ "Two players, A and B, play a game on a row of 2018 squares numbered from 0 to 2017. Initially, a coin is placed on square 0. Players take turns moving the coin either 53 squares forward or 2 squares backward, without going beyond the bounds of the row. The player who places the coin on square 2017 wins. Determine ...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect" ]
{ "cot": 11, "genselect": 3 }
14
0
0
omr-ws-f8f45700e44a56168b095c06b02ce49fc210cbb8def455c22087fc66f8ca7338
Two players, A and B, play a game on a row of 2018 squares numbered from 0 to 2017. Initially, a coin is placed on square 0. Players take turns, starting with A, and on each turn, a player can either move the coin forward by 53 squares or backward by 2 squares. The coin cannot move to a number less than 0 or greater th...
[ "A" ]
[ "Two players, A and B, play a game on a row of 2018 squares numbered from 0 to 2017. Initially, a coin is placed on square 0. Players take turns, starting with A, and on each turn, a player can either move the coin forward by 53 squares or backward by 2 squares. The coin cannot move to a number less than 0 or great...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect" ]
{ "cot": 11, "genselect": 2 }
13
0
0
omr-ws-2214b24d4732733ae219f0ab201597c96f8bf853af053c52120bca441215685e
Two players, A and B, play a game on a row of 2018 squares numbered from 0 to 2017. Initially, a coin is placed on square 0. Players take turns, starting with A, and on each turn, a player can either move the coin forward by 53 squares or backward by 2 squares. The coin cannot move to a position less than 0 or greater ...
[ "Player A has the winning strategy." ]
[ "Two players, A and B, play a game on a row of 2018 squares numbered from 0 to 2017. Initially, a coin is placed on square 0. Players take turns, starting with A, and on each turn, a player can either move the coin forward by 53 squares or backward by 2 squares. The coin cannot move to a position less than 0 or gre...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect", "tir" ]
{ "cot": 7, "genselect": 3, "tir": 2 }
12
0
0
omr-ws-4deb48cb1517b18f71ddec47ac08ef95d1a20f26f52f70955016845daba03f0d
Two players, A and B, play a game over $n > 1$ rounds with a fixed integer $d \geq 1$. In the first round, A picks a positive integer $m_1$, and B picks a positive integer $n_1 \neq m_1$. In each subsequent round $k$ (for $k = 2, \ldots, n$), A picks an integer $m_k$ such that $m_{k-1} < m_k \leq m_{k-1} + d$, and B pi...
[ "B always has a winning strategy." ]
[ "Two players, A and B, play a game over $n > 1$ rounds with a fixed integer $d \\geq 1$. In the first round, A picks a positive integer $m_1$, and B picks a positive integer $n_1 \\neq m_1$. In each subsequent round $k$ (for $k = 2, \\ldots, n$), A picks an integer $m_k$ such that $m_{k-1} < m_k \\leq m_{k-1} + d$,...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect" ]
{ "cot": 3, "genselect": 2 }
5
0
0
omr-ws-e39486bdbc90807867c4d87ad63e7ca69129f2a575dfdb246693e0f8d40b99d3
Two players, A and B, play a game starting with a positive integer \( N \). On each turn, a player can either subtract 1 from the number or, if the number is even, halve the number. A goes first, followed by B, and they alternate turns. The player who reduces the number to 0 wins. Assuming both players play optimally, ...
[ "A can win when the starting number is 1, 3, or any even number greater than 2." ]
[ "Two players, A and B, play a game starting with a positive integer \\( N \\). On each turn, a player can either subtract 1 from the number or, if the number is even, halve the number. A goes first, followed by B, and they alternate turns. The player who reduces the number to 0 wins. Assuming both players play opti...
[ "aops_c4_high_school_math", "c4_high_school_math" ]
[ "cot", "genselect", "tir" ]
{ "cot": 14, "genselect": 8, "tir": 19 }
41
0
0
omr-ws-8e9744ac8aa28f7eaf0422d3f6d69c3d7d4a2f0d4981532e955feb96dc7082ec
Two players, A and B, play a game starting with a positive integer \( N_0 \) on the blackboard. A erases \( N_0 \) and writes \( N_1 \in \{N_0 - 1, \lfloor N_0 / 3 \rfloor\} \). B erases \( N_1 \) and writes \( N_2 \in \{N_1 - 1, \lfloor N_1 / 3 \rfloor\} \). They continue until 0 appears on the blackboard. The player ...
[ "B" ]
[ "Two players, A and B, play a game starting with a positive integer \\( N_0 \\) on the blackboard. A erases \\( N_0 \\) and writes \\( N_1 \\in \\{N_0 - 1, \\lfloor N_0 / 3 \\rfloor\\} \\). B erases \\( N_1 \\) and writes \\( N_2 \\in \\{N_1 - 1, \\lfloor N_1 / 3 \\rfloor\\} \\). They continue until 0 appears on th...
[ "aops_c6_high_school_olympiads" ]
[ "cot" ]
{ "cot": 16 }
16
0
0
omr-ws-9239e97126a704687d816f9c10361aa4f7636ce95f35b6dd9a781d4ee172de59
Two players, A and B, play a game starting with a positive integer \( N_0 \) on the blackboard. A erases \( N_0 \) and writes \( N_1 \in \{N_0 - 1, \lfloor N_0 / 3 \rfloor\} \). B erases \( N_1 \) and writes \( N_2 \in \{N_1 - 1, \lfloor N_1 / 3 \rfloor\} \). They continue until 0 appears on the blackboard. The player ...
[ "B" ]
[ "Two players, A and B, play a game starting with a positive integer \\( N_0 \\) on the blackboard. A erases \\( N_0 \\) and writes \\( N_1 \\in \\{N_0 - 1, \\lfloor N_0 / 3 \\rfloor\\} \\). B erases \\( N_1 \\) and writes \\( N_2 \\in \\{N_1 - 1, \\lfloor N_1 / 3 \\rfloor\\} \\). They continue until 0 appears on th...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect" ]
{ "cot": 14, "genselect": 7 }
21
0
0
omr-ws-41a4d28db358cdc2577e5af54facabba2d813409ab2bff3b6f0636fd0879eb62
Two players, A and B, play a game starting with a positive integer \( N_0 \) on the blackboard. A erases \( N_0 \) and writes \( N_1 \in \{N_0 - 1, \lfloor N_0 / 3 \rfloor\} \). B erases \( N_1 \) and writes \( N_2 \in \{N_1 - 1, \lfloor N_1 / 3 \rfloor\} \). They continue until 0 appears on the blackboard. The player ...
[ "A" ]
[ "Two players, A and B, play a game starting with a positive integer \\( N_0 \\) on the blackboard. A erases \\( N_0 \\) and writes \\( N_1 \\in \\{N_0 - 1, \\lfloor N_0 / 3 \\rfloor\\} \\). B erases \\( N_1 \\) and writes \\( N_2 \\in \\{N_1 - 1, \\lfloor N_1 / 3 \\rfloor\\} \\). They continue until 0 appears on th...
[ "aops_c6_high_school_olympiads" ]
[ "cot" ]
{ "cot": 16 }
16
0
0
omr-ws-a2ac153555454b5da72db33221b9ad6cecfe60fe5ae8c870ef2dfe80f3a7d9d6
Two players, A and B, play a game starting with the number \(2017^{2017}\). On each turn, a player can either subtract an integer between 1 and 2016 (inclusive) or divide the number by 2017, rounding down to the nearest integer. The player who first obtains a non-positive integer wins. Which player has a winning strate...
[ "A" ]
[ "Two players, A and B, play a game starting with the number \\(2017^{2017}\\). On each turn, a player can either subtract an integer between 1 and 2016 (inclusive) or divide the number by 2017, rounding down to the nearest integer. The player who first obtains a non-positive integer wins. Which player has a winning...
[ "aops_c4_high_school_math" ]
[ "tir" ]
{ "tir": 2 }
2
0
0
omr-ws-74cc9fe07f1270ad830144ed87dcbee2628f75aa3f596bb4f290a5aa318c51c7
Two players, A and B, play a game where they repeatedly flip a coin. If the coin lands on heads (with probability \( p \)), B gives A one unit. If the coin lands on tails (with probability \( 1 - p \)), A gives B one unit. Initially, A has \( i \) units and B has \( N - i \) units. What is the probability that A wins (...
[ "\\( \\frac{(1-p)^N - p^{N-i}(1-p)^i}{(1-p)^N - p^N} \\)" ]
[ "Two players, A and B, play a game where they repeatedly flip a coin. If the coin lands on heads (with probability \\( p \\)), B gives A one unit. If the coin lands on tails (with probability \\( 1 - p \\)), A gives B one unit. Initially, A has \\( i \\) units and B has \\( N - i \\) units. What is the probability ...
[ "aops_c7_college_math" ]
[ "cot", "genselect", "tir" ]
{ "cot": 2, "genselect": 1, "tir": 10 }
13
0
0
omr-ws-43150b67058b552463675a799bba10d82827a03490ff9d6bae6ea1f93a078ec3
Two players, A and B, play a game with 101 numbers on a board (1 through 101). In each turn, a player erases 9 numbers. After 11 turns (with A playing 6 turns and B playing 5 turns), two numbers remain. Player A aims to maximize the difference between these two numbers, while player B aims to minimize it. Determine the...
[ "55" ]
[ "Two players, A and B, play a game with 101 numbers on a board (1 through 101). In each turn, a player erases 9 numbers. After 11 turns (with A playing 6 turns and B playing 5 turns), two numbers remain. Player A aims to maximize the difference between these two numbers, while player B aims to minimize it. Determin...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect" ]
{ "cot": 35, "genselect": 7 }
42
0
0
omr-ws-e672a631685ea2afdf6347cb833f129fab69eac365911eb883c92832d6d4b109
Two players, A and B, play a game with \( n \) piles of stones. Player A starts by choosing 2 piles, then player B takes an arbitrary (but nonzero) number of stones from one of the 2 chosen piles. Then player B selects 2 piles, and player A takes some stones from one of them. The player who removes the last stone wins....
[ "Player A has a winning strategy if there is an even number of smallest piles; otherwise, player B has a winning strategy." ]
[ "Two players, A and B, play a game with \\( n \\) piles of stones. Player A starts by choosing 2 piles, then player B takes an arbitrary (but nonzero) number of stones from one of the 2 chosen piles. Then player B selects 2 piles, and player A takes some stones from one of them. The player who removes the last ston...
[ "aops_c6_high_school_olympiads" ]
[ "additional_problems" ]
{ "additional_problems": 1 }
1
0
0
omr-ws-60cd4592c58ad327511aaa11ef4dd8d894169245a07308ea71ed9920dd936f7b
Two players, A and B, play a game with a pile of 2006 coins. Players take turns removing between 1 and 7 coins each turn. A player can also choose to pass their turn but must pay 7 coins from their previously collected coins to a separate box. The player who takes the last coin wins, and A starts the game. Determine wh...
[ "Player A can win for sure." ]
[ "Two players, A and B, play a game with a pile of 2006 coins. Players take turns removing between 1 and 7 coins each turn. A player can also choose to pass their turn but must pay 7 coins from their previously collected coins to a separate box. The player who takes the last coin wins, and A starts the game. Determi...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "tir" ]
{ "cot": 9, "tir": 16 }
25
0
0
omr-ws-573ecb91f31fc462ad9b1c64aa9a4c8203402d7c651d97c6cacfbac239689756
Two players, A and B, play a game with a regular convex polygon with $2n+1$ edges, where $n > 1$. Player A starts and each player takes turns coloring one uncolored vertex. The player who makes it impossible for the other to form an acute triangle with the remaining uncolored vertices wins. Determine which player has t...
[ "A" ]
[ "Two players, A and B, play a game with a regular convex polygon with $2n+1$ edges, where $n > 1$. Player A starts and each player takes turns coloring one uncolored vertex. The player who makes it impossible for the other to form an acute triangle with the remaining uncolored vertices wins. Determine which player ...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect" ]
{ "cot": 11, "genselect": 7 }
18
0
0
omr-ws-afd65ae7d347298b38b009a2a1750d8c18375ab8cf38e8d88e537424eaec0b89
Two players, A and B, play a game with five jugs numbered 0 through 4. Jug 0 is empty, and each of the other jugs contains some number of coins. On each turn, a player can move any number of coins (at least one) from any jug to the jug numbered one less. Player A starts. The player who makes the last move, resulting in...
[ "B" ]
[ "Two players, A and B, play a game with five jugs numbered 0 through 4. Jug 0 is empty, and each of the other jugs contains some number of coins. On each turn, a player can move any number of coins (at least one) from any jug to the jug numbered one less. Player A starts. The player who makes the last move, resulti...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect" ]
{ "cot": 11, "genselect": 5 }
16
0
0
omr-ws-cab12e8689742aa83728aa819834e25f71ad984b6003c4ac4e7dd09ca1b248dd
Two players, A and B, play a game with two piles of 2010 coins each. Players take turns, with A going first. On each turn, a player can take one or more coins from one pile or exactly one coin from each pile. The player who takes the last coin wins. Which player will win if both play optimally?
[ "B wins." ]
[ "Two players, A and B, play a game with two piles of 2010 coins each. Players take turns, with A going first. On each turn, a player can take one or more coins from one pile or exactly one coin from each pile. The player who takes the last coin wins. Which player will win if both play optimally?" ]
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect", "tir" ]
{ "cot": 13, "genselect": 3, "tir": 11 }
27
0
0
omr-ws-3a597fbba15576e0d8a818127737d6e9e217f04a3637d5742a33e4107a904eca
Two players, A and B, play a game with two piles of stones. In each round, the current player chooses a positive integer \( k \) and removes \( k \) stones from one of the piles (if \( k \) exceeds the number of stones in the chosen pile, the player takes all the stones). The player who takes the last stone loses. Dete...
[ "A has a winning strategy if adding \\(a-1\\) and \\(b-1\\) in binary involves no carry-forwards. The strategy for A is to ensure that after each of their moves, adding the updated pile sizes minus one involves a carry-forward." ]
[ "Two players, A and B, play a game with two piles of stones. In each round, the current player chooses a positive integer \\( k \\) and removes \\( k \\) stones from one of the piles (if \\( k \\) exceeds the number of stones in the chosen pile, the player takes all the stones). The player who takes the last stone ...
[ "aops_c6_high_school_olympiads" ]
[ "additional_problems" ]
{ "additional_problems": 1 }
1
0
0
omr-ws-5780bdea683f8e2174054b87bedd99aa48f8910a798913adb7b241024dc2ff24
Two players, A and B, start with the number 60 on a board. In each move, a player subtracts any positive divisor (including 1 and the number itself) from the current number and replaces it with the difference. Player A starts first. The player who reaches 0 loses. Determine who will win and provide a winning strategy f...
[ "Player A wins. Strategy: Always subtract an odd divisor." ]
[ "Two players, A and B, start with the number 60 on a board. In each move, a player subtracts any positive divisor (including 1 and the number itself) from the current number and replaces it with the difference. Player A starts first. The player who reaches 0 loses. Determine who will win and provide a winning strat...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "tir" ]
{ "cot": 47, "tir": 13 }
60
0
0
omr-ws-e8f8ecf499fe26fb98ddc35a3de69a314b5cccb20594f5f5761173d3ad2552d5
Two players, A and B, take turns filling in the coefficients of the polynomial \( f(X) = X^{10} + ?X^9 + ?X^8 + \ldots + 1 \). If the resulting polynomial \( f(X) \) has no real roots, A wins. If \( f(X) \) has real roots, B wins. A goes first. Determine who has a winning strategy and describe the strategy.
[ "A has a winning strategy." ]
[ "Two players, A and B, take turns filling in the coefficients of the polynomial \\( f(X) = X^{10} + ?X^9 + ?X^8 + \\ldots + 1 \\). If the resulting polynomial \\( f(X) \\) has no real roots, A wins. If \\( f(X) \\) has real roots, B wins. A goes first. Determine who has a winning strategy and describe the strategy....
[ "aops_c6_high_school_olympiads" ]
[ "genselect" ]
{ "genselect": 2 }
2
0
0
omr-ws-f13ce5e1535c383fcd04063af51241ffb9470d841124b8f8aafb2c8965b09e90
Two players, A and B, take turns removing chips from a pile that initially contains \( n \) chips. Player A cannot remove all chips on his first turn and must remove at least one chip. Thereafter, a player can remove up to twice the number of chips removed by the opponent on the previous turn. The player who removes th...
[ "n - f" ]
[ "Two players, A and B, take turns removing chips from a pile that initially contains \\( n \\) chips. Player A cannot remove all chips on his first turn and must remove at least one chip. Thereafter, a player can remove up to twice the number of chips removed by the opponent on the previous turn. The player who rem...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect" ]
{ "cot": 10, "genselect": 6 }
16
0
0
omr-ws-fb91a438dafebea29c9194714859274637c008729f0b7883939804b598d5d17c
Two players, A and B, take turns removing chips from a pile that initially contains \( n \) chips. Player A cannot remove all chips on his first turn and must remove at least one chip. Thereafter, a player cannot remove more chips than the opponent removed on the previous turn. The player who removes the last chip wins...
[ "A wins if \\( n \\) is not a power of 2." ]
[ "Two players, A and B, take turns removing chips from a pile that initially contains \\( n \\) chips. Player A cannot remove all chips on his first turn and must remove at least one chip. Thereafter, a player cannot remove more chips than the opponent removed on the previous turn. The player who removes the last ch...
[ "aops_c6_high_school_olympiads" ]
[ "tir" ]
{ "tir": 20 }
20
0
0
omr-ws-1eb89087189f677f6febb41691ddc60eae853a7e6e946771b481ccc0ed27e12f
Two players, A and B, take turns removing stones from a heap with at least 2 stones. Player A starts and can take between 1 and n-1 stones. Each subsequent player must take between 1 and the number of stones the previous player took. The player who takes the last stone wins. Determine which player has a winning strateg...
[ "Player B has a winning strategy if \\( n \\) is a power of 2; otherwise, player A has a winning strategy." ]
[ "Two players, A and B, take turns removing stones from a heap with at least 2 stones. Player A starts and can take between 1 and n-1 stones. Each subsequent player must take between 1 and the number of stones the previous player took. The player who takes the last stone wins. Determine which player has a winning st...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect", "tir" ]
{ "cot": 3, "genselect": 4, "tir": 23 }
30
0
0
omr-ws-f709db514388b756e1205f95605b63674f5bb3de36bffe0757151d5828b06eb5
Two players, A and B, take turns writing composite divisors of \( N = p_1 p_2 \cdots p_n \), where \( p_1, p_2, \ldots, p_n \) are distinct primes. The rule is that no two numbers written should be such that one divides the other. Player A starts the game. Determine who can win the game.
[ "A wins." ]
[ "Two players, A and B, take turns writing composite divisors of \\( N = p_1 p_2 \\cdots p_n \\), where \\( p_1, p_2, \\ldots, p_n \\) are distinct primes. The rule is that no two numbers written should be such that one divides the other. Player A starts the game. Determine who can win the game." ]
[ "aops_c6_high_school_olympiads" ]
[ "cot", "tir" ]
{ "cot": 16, "tir": 15 }
31
0
0
omr-ws-35a86ad7c557b352d1361f596744820ed5a8dca70871700565305dc480b3c244
Two players, Alice and Bob, play a game on a \( 10 \times 10 \) grid. Initially, all cells are empty. Alice and Bob take turns placing a single coin in an empty cell, with Alice starting first. The game ends when a player cannot make a move. The player who cannot make a move loses. Determine which player has a winning ...
[ "Bob has a winning strategy." ]
[ "Two players, Alice and Bob, play a game on a \\( 10 \\times 10 \\) grid. Initially, all cells are empty. Alice and Bob take turns placing a single coin in an empty cell, with Alice starting first. The game ends when a player cannot make a move. The player who cannot make a move loses. Determine which player has a ...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "tir" ]
{ "cot": 16, "tir": 28 }
44
0
0
omr-ws-05bbe6ed44d1972e63b7e98fc95f8a4c629edc783cb04c164afda7f7d6cfe7d9
Two players, Alice and Bob, play a game starting with the number $10^{2018}$ on a blackboard. The players take turns performing one of two actions: 1. Divide a number $x$ on the board into integers $a$ and $b$ such that $ab = x$. 2. If a number $x$ occurs twice, erase one or both instances. The player who cannot make a...
[ "Alice has a winning strategy." ]
[ "Two players, Alice and Bob, play a game starting with the number $10^{2018}$ on a blackboard. The players take turns performing one of two actions:\n1. Divide a number $x$ on the board into integers $a$ and $b$ such that $ab = x$.\n2. If a number $x$ occurs twice, erase one or both instances.\n\nThe player who can...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "tir" ]
{ "cot": 6, "tir": 6 }
12
0
0
omr-ws-3cb868c5bb12f507c8ffc71d61b346640bcfe6071e4586656d58eafc2c04e4b7
Two players, Ana and Ben, are playing a game on a 4x4 grid of points with integer coordinates $(m,n)$ where $1 \leq m, n \leq 4$. Ana starts by coloring one point red, then Ben colors one of the remaining points yellow, and they alternate turns. The first player to create a rectangle with vertices of the same color and...
[ "Ben" ]
[ "Two players, Ana and Ben, are playing a game on a 4x4 grid of points with integer coordinates $(m,n)$ where $1 \\leq m, n \\leq 4$. Ana starts by coloring one point red, then Ben colors one of the remaining points yellow, and they alternate turns. The first player to create a rectangle with vertices of the same co...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect" ]
{ "cot": 9, "genselect": 2 }
11
0
0
omr-ws-b599b72e7b2338ec16138020aae3d50d700f0417f7e201c66f99a92c215e48d9
Two players, Ana and Bogdan, play a game with 2017 pebbles on a table. Ana starts by taking one pebble. On each subsequent turn, the player can take between 1 and \(2^{(j-1)}\) pebbles, where \(j\) is the turn number. The player who takes the last pebble wins. Determine which player has a winning strategy.
[ "Ana" ]
[ "Two players, Ana and Bogdan, play a game with 2017 pebbles on a table. Ana starts by taking one pebble. On each subsequent turn, the player can take between 1 and \\(2^{(j-1)}\\) pebbles, where \\(j\\) is the turn number. The player who takes the last pebble wins. Determine which player has a winning strategy." ]
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect" ]
{ "cot": 13, "genselect": 3 }
16
0
0
omr-ws-b4c4bcd4f7d03dcffca5eb23a436c89a4bc54d83c091755c9d028d00fb6599d1
Two players, Andria and Bob, are playing a game with two piles of stones containing $x$ and $y$ stones respectively. Andria moves first. On each turn, a player can remove $k$ stones from one pile, where $k$ must be divisible by the number of stones in the other pile. The player who takes the last stone wins. Find a win...
[ "\\text{The first player wins if the number of steps in the Euclidean algorithm for gcd}(x, y) \\text{ is odd.}" ]
[ "Two players, Andria and Bob, are playing a game with two piles of stones containing $x$ and $y$ stones respectively. Andria moves first. On each turn, a player can remove $k$ stones from one pile, where $k$ must be divisible by the number of stones in the other pile. The player who takes the last stone wins. Find ...
[ "aops_c6_high_school_olympiads" ]
[ "additional_problems", "genselect" ]
{ "additional_problems": 1, "genselect": 4 }
5
0
0
omr-ws-49058cefc89892e25b2de3f5ee24d5e0edb6a4fa0d8715d35cad9be37456f6c1
Two players, Andriy and Olesya, play a game with a round cake cut into $2n$ ($n>1$) sectors of distinct weights. Olesya takes 1 piece first, then Andriy takes 2 pieces such that the remaining pieces form a sector. They continue taking 2 pieces each turn, ensuring the remaining pieces form a sector, until one player tak...
[ "\\( n \\neq 2, 4 \\)" ]
[ "Two players, Andriy and Olesya, play a game with a round cake cut into $2n$ ($n>1$) sectors of distinct weights. Olesya takes 1 piece first, then Andriy takes 2 pieces such that the remaining pieces form a sector. They continue taking 2 pieces each turn, ensuring the remaining pieces form a sector, until one playe...
[ "aops_c6_high_school_olympiads" ]
[ "cot" ]
{ "cot": 1 }
1
0
0
omr-ws-5e5ac946821ee8820cf101b46cf56c9417e377a75875e615fd84fcfe1ded9638
Two players, Anne and Berit, play a game starting with the number $10^{2007}$ on the blackboard. On each turn, a player can either replace a number $x$ with two integers $a, b > 1$ such that $ab = x$, or strike off one or both of two equal numbers on the blackboard. The player who cannot perform any operation loses. Wh...
[ "Anne has the winning strategy." ]
[ "Two players, Anne and Berit, play a game starting with the number $10^{2007}$ on the blackboard. On each turn, a player can either replace a number $x$ with two integers $a, b > 1$ such that $ab = x$, or strike off one or both of two equal numbers on the blackboard. The player who cannot perform any operation lose...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect", "tir" ]
{ "cot": 6, "genselect": 1, "tir": 8 }
15
0
0
omr-ws-64fddcc5c79c2198dc31e6ae97e7e47472071ce2ed629a31feeee9721bd16cb0
Two players, Arnaldo and Betania, play alternately with Arnaldo starting first. Initially, there are two piles of stones containing $x$ and $y$ stones respectively. In each turn, a player can either: 1. Choose two non-empty piles and take one stone from each pile. 2. Choose a pile with an odd amount of stones, take one...
[ "Arnaldo wins if $x \\equiv y \\pmod{2}$ and both are odd, or if $x \\equiv 1 \\pmod{4}$ and $y$ is even, or if $x \\equiv 3 \\pmod{4}$ and $y \\equiv 0 \\pmod{4}$. Betania wins if $x \\equiv y \\pmod{2}$ and both are even, or if $x \\equiv 3 \\pmod{4}$ and $y \\equiv 2 \\pmod{4}$." ]
[ "Two players, Arnaldo and Betania, play alternately with Arnaldo starting first. Initially, there are two piles of stones containing $x$ and $y$ stones respectively. In each turn, a player can either:\n1. Choose two non-empty piles and take one stone from each pile.\n2. Choose a pile with an odd amount of stones, t...
[ "aops_c6_high_school_olympiads" ]
[ "additional_problems" ]
{ "additional_problems": 1 }
1
0
0
omr-ws-873f0f1731f8c51372cb4fdb0184869643ffa18890ccad365c1aa431804af3db
Two players, Arnould and Betty, play alternately with Arnould starting first. Initially, there are two piles of stones containing \( x \) and \( y \) stones, respectively. In each move, a player can: 1. Choose two non-empty piles and take one stone from each. 2. Choose a pile with an odd number of stones, take one ston...
[ "Arnould" ]
[ "Two players, Arnould and Betty, play alternately with Arnould starting first. Initially, there are two piles of stones containing \\( x \\) and \\( y \\) stones, respectively. In each move, a player can:\n1. Choose two non-empty piles and take one stone from each.\n2. Choose a pile with an odd number of stones, ta...
[ "aops_c4_high_school_math" ]
[ "cot" ]
{ "cot": 6 }
6
0
0
omr-ws-83341a85aa865acc21881a18fd29cb60fccd2528b83f4f9d36350074ee8e44bf
Two players, Aryan and Anurag, alternately move a marble on a coordinate plane starting from the origin \(O(0,0)\). The marble must stay within the circle with diameter \(OB\), where \(B\) is at \((5,0)\). On each turn, the marble must be moved to a new position \((c,d)\) such that the distance from the current positio...
[ "Aryan has the winning strategy." ]
[ "Two players, Aryan and Anurag, alternately move a marble on a coordinate plane starting from the origin \\(O(0,0)\\). The marble must stay within the circle with diameter \\(OB\\), where \\(B\\) is at \\((5,0)\\). On each turn, the marble must be moved to a new position \\((c,d)\\) such that the distance from the ...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect", "tir" ]
{ "cot": 6, "genselect": 6, "tir": 8 }
20
0
0
omr-ws-7ae0b50c3aac4e733a46d24214cd2c350bfddf77589a80751bde164d7f43ef7b
Two players, Diego and Pablo, play a game with a ladder sequence $1, 2, \dots, 2020$. On each turn, a player replaces an entry $a_i$ with a smaller non-negative integer $a_i'$ such that the sequence remains non-decreasing. The player who first achieves the sequence $(0, 0, \dots, 0)$ wins. Determine which player has a ...
[ "Pablo has a winning strategy." ]
[ "Two players, Diego and Pablo, play a game with a ladder sequence $1, 2, \\dots, 2020$. On each turn, a player replaces an entry $a_i$ with a smaller non-negative integer $a_i'$ such that the sequence remains non-decreasing. The player who first achieves the sequence $(0, 0, \\dots, 0)$ wins. Determine which player...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect", "tir" ]
{ "cot": 19, "genselect": 5, "tir": 11 }
35
0
0
omr-ws-ffc37bfc19c38694edf300a03ee7ef212d301ee285228ff817c1514339ec8e54
Two players, F and S, are playing a game with a fair coin. Player F wins if there are two tails in a row, and player S wins if there are three heads in a row. What is the probability that player F will win the game?
[ "\\(\\frac{7}{10}\\)", "\\dfrac{7}{10}" ]
[ "Two players, F and S, are playing a game with a fair coin. Player F wins if there are two tails in a row, and player S wins if there are three heads in a row. What is the probability that player F will win the game?" ]
[ "aops_c4_high_school_math", "aops_c6_high_school_olympiads", "c4_high_school_math" ]
[ "cot", "tir" ]
{ "cot": 47, "tir": 22 }
69
0
0
omr-ws-12b0cced15282ac258f3e6e0023393674ab2680d803566390103561ca175a777
Two players, Jacob and David, play a game in a convex polygon with $n \geq 5$ sides. On each turn, they draw a diagonal which does not intersect any previously drawn diagonal. The player that creates a quadrilateral (with no diagonal yet drawn) loses. If Jacob plays first, for which values of $n$ can he win?
[ "\\( n \\) is even." ]
[ "Two players, Jacob and David, play a game in a convex polygon with $n \\geq 5$ sides. On each turn, they draw a diagonal which does not intersect any previously drawn diagonal. The player that creates a quadrilateral (with no diagonal yet drawn) loses. If Jacob plays first, for which values of $n$ can he win?" ]
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect", "tir" ]
{ "cot": 19, "genselect": 3, "tir": 7 }
29
0
0
omr-ws-9e4588262265aae52db9d4a3f65f934c508d882b2dd21d8802bbce808457bdab
Two players, Mathinity and Golden Math, take turns filling in the blanks with real numbers in the polynomial \(x^{69} + \_\_\_\_ x^{68} + \_\_\_\_ x^{67} + \ldots + \_\_\_\_ x + \_\_\_\_\). Mathinity goes first. If the resulting polynomial has at least 3 distinct real roots, Mathinity wins; otherwise, Golden Math wins....
[ "Mathinity" ]
[ "Two players, Mathinity and Golden Math, take turns filling in the blanks with real numbers in the polynomial \\(x^{69} + \\_\\_\\_\\_ x^{68} + \\_\\_\\_\\_ x^{67} + \\ldots + \\_\\_\\_\\_ x + \\_\\_\\_\\_\\). Mathinity goes first. If the resulting polynomial has at least 3 distinct real roots, Mathinity wins; othe...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect" ]
{ "cot": 9, "genselect": 5 }
14
0
0
omr-ws-f68e181d74350346a4f05410ce29cd86bbe663da2fd621bd1d782a27305ecf5c
Two players, Red and Blue, play on a 10x10 board in alternating turns. Blue goes first. In each turn, a player picks an unchosen row or column and colors all its squares with their own color, overwriting any previous colors. The game ends after 20 turns when all rows and columns are chosen. Red wins if the number of re...
[ "Red" ]
[ "Two players, Red and Blue, play on a 10x10 board in alternating turns. Blue goes first. In each turn, a player picks an unchosen row or column and colors all its squares with their own color, overwriting any previous colors. The game ends after 20 turns when all rows and columns are chosen. Red wins if the number ...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "tir" ]
{ "cot": 15, "tir": 5 }
20
0
0
omr-ws-e574d244a3d253e8e62736a7e3028845abb04ccebf311367949d0dabd6221b82
Two players, S and G, play a game on a $2017 \times n$ board. The first player, S, picks a square of size $k \times k$ and colors it. The next player, G, then picks another uncolored $k \times k$ square and colors it. They take turns coloring squares until one player cannot make a move, at which point the other player ...
[ "All integers \\( n \\geq 2017 \\)" ]
[ "Two players, S and G, play a game on a $2017 \\times n$ board. The first player, S, picks a square of size $k \\times k$ and colors it. The next player, G, then picks another uncolored $k \\times k$ square and colors it. They take turns coloring squares until one player cannot make a move, at which point the other...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "tir" ]
{ "cot": 1, "tir": 5 }
6
0
0
omr-ws-9052814422dd81b383369eefc11086c17401e0216503a972ecaaf8486506ad77
Two players, SB and RH, play a game starting with the number \(10^{2007}\) on the board. The players take turns performing one of the following actions: 1. Choose a number \(x\) on the board and replace it with two numbers \(a\) and \(b\) such that \(ab = x\). 2. If there are two identical numbers on the board, erase o...
[ "SB wins." ]
[ "Two players, SB and RH, play a game starting with the number \\(10^{2007}\\) on the board. The players take turns performing one of the following actions:\n1. Choose a number \\(x\\) on the board and replace it with two numbers \\(a\\) and \\(b\\) such that \\(ab = x\\).\n2. If there are two identical numbers on t...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect", "tir" ]
{ "cot": 4, "genselect": 1, "tir": 1 }
6
0
0
omr-ws-c8447cffc479d0b7ccc41debd73ccd89ea05e50adc2cc3d6c454921f1ef2807a
Two players, Tom and Sid, play a game with two piles of rocks. The first pile has 10 rocks, and the second pile has 12 rocks. Each player, on their turn, can take any amount of rocks from one pile or the same amount of rocks from both piles. The player who takes the last rock wins. Who wins if Tom starts the game?
[ "Tom wins." ]
[ "Two players, Tom and Sid, play a game with two piles of rocks. The first pile has 10 rocks, and the second pile has 12 rocks. Each player, on their turn, can take any amount of rocks from one pile or the same amount of rocks from both piles. The player who takes the last rock wins. Who wins if Tom starts the game?...
[ "aops_c4_high_school_math" ]
[ "cot", "tir" ]
{ "cot": 16, "tir": 18 }
34
0
0
omr-ws-b09d67b2672433b5bbe7d555b732540288d8bb41c63df47ce2dd3e86fd0287de
Two players, Wester Olfram and Peter Enis, are playing a game. Initially, there are $2021$ times the integer $69$ written on a blackboard. Wester begins the game and the players move alternately. The player who is currently making a move chooses one of the non-zero numbers on the board. If this number $n$ is the smalle...
[ "Wester Olfram" ]
[ "Two players, Wester Olfram and Peter Enis, are playing a game. Initially, there are $2021$ times the integer $69$ written on a blackboard. Wester begins the game and the players move alternately. The player who is currently making a move chooses one of the non-zero numbers on the board. If this number $n$ is the s...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect", "tir" ]
{ "cot": 14, "genselect": 7, "tir": 24 }
45
0
0
omr-ws-34b680a23bb53977f23173b97bccf85423f3d541263047023981a7814654595a
Two players, X and Y, play a game consisting of multiple matches. The probability that X wins a match is $\frac{1}{2}$, the probability that Y wins a match is $\frac{1}{4}$, and the probability of a draw is $\frac{1}{4}$. They continue playing until either X or Y wins two consecutive matches. Let $P(X)$ be the probabil...
[ "\\( a = \\frac{16}{21} \\), \\( b = \\frac{5}{21} \\)" ]
[ "Two players, X and Y, play a game consisting of multiple matches. The probability that X wins a match is $\\frac{1}{2}$, the probability that Y wins a match is $\\frac{1}{4}$, and the probability of a draw is $\\frac{1}{4}$. They continue playing until either X or Y wins two consecutive matches. Let $P(X)$ be the ...
[ "aops_c7_college_math" ]
[ "additional_problems" ]
{ "additional_problems": 1 }
1
0
0
omr-ws-159f0d0a71dde1a069bffa50f5e596a1fbffe40e4363c8bf161a2114d47617e1
Two players, \( A \) and \( B \), play a game on a circle with 10 cells. Player \( A \) starts, and they take turns choosing a free cell and writing either \( O \) or \( M \) in it. The player who first creates the sequence \( OMO \) in three consecutive cells wins. If no such sequence is formed, the game is a draw. As...
[ "0" ]
[ "Two players, \\( A \\) and \\( B \\), play a game on a circle with 10 cells. Player \\( A \\) starts, and they take turns choosing a free cell and writing either \\( O \\) or \\( M \\) in it. The player who first creates the sequence \\( OMO \\) in three consecutive cells wins. If no such sequence is formed, the g...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect" ]
{ "cot": 5, "genselect": 4 }
9
0
0
omr-ws-b513f8a36adde523d6936c1dd0340e7ec4bb4d3144b89915ad11850b9f3c3c80
Two players, \(A\) (first player) and \(B\), take alternate turns in playing a game using 2016 chips. On each turn, a player must remove \(s\) chips from the remaining pile, where \(s \in \{ 2, 4, 5 \}\). The player who is unable to make a move loses the game. Determine which player can force a win.
[ "Player \\(B\\) can force a win." ]
[ "Two players, \\(A\\) (first player) and \\(B\\), take alternate turns in playing a game using 2016 chips. On each turn, a player must remove \\(s\\) chips from the remaining pile, where \\(s \\in \\{ 2, 4, 5 \\}\\). The player who is unable to make a move loses the game. Determine which player can force a win." ]
[ "aops_c6_high_school_olympiads" ]
[ "cot", "tir" ]
{ "cot": 16, "tir": 21 }
37
0
0
omr-ws-ec4b264f33ab319590869b18adae1d0d105ac0d9bc9ed9797292e76a28cf7cf7
Two players, \(A\) and \(B\), play a game starting with the number \(10^{2007}\) on the blackboard. On each turn, a player can either: - Replace a number \(x\) on the blackboard by two integers \(a\) and \(b\) greater than 1 such that \(ab = x\), or - Strike off one or both of two equal numbers on the blackboard. The p...
[ "A will win." ]
[ "Two players, \\(A\\) and \\(B\\), play a game starting with the number \\(10^{2007}\\) on the blackboard. On each turn, a player can either:\n- Replace a number \\(x\\) on the blackboard by two integers \\(a\\) and \\(b\\) greater than 1 such that \\(ab = x\\), or\n- Strike off one or both of two equal numbers on ...
[ "aops_c6_high_school_olympiads" ]
[ "cot" ]
{ "cot": 5 }
5
0
0
omr-ws-93bde43ef2843818718b4ca7bf590253536694940f4f806e5796e60ed96cd17f
Two players, \(A\) and \(B\), play a game with 400 numbers written on a board. On each turn, a player erases three numbers that can form the sides of a triangle. Player \(A\) goes first. The player who cannot make a move loses. Determine which player has a winning strategy.
[ "A" ]
[ "Two players, \\(A\\) and \\(B\\), play a game with 400 numbers written on a board. On each turn, a player erases three numbers that can form the sides of a triangle. Player \\(A\\) goes first. The player who cannot make a move loses. Determine which player has a winning strategy." ]
[ "aops_c6_high_school_olympiads" ]
[ "cot" ]
{ "cot": 16 }
16
0
0
omr-ws-632d6056f6d088c844f4402cffd43e5d5d159d2b990c1285195d9fae3663f723
Two players, \(A\) and \(B\), play a game with \(2n\) cards. Each card has a positive integer written on it. The cards are shuffled and laid out in a row with the numbers facing upwards. \(A\) starts and the players take turns to remove one card from either end of the row until \(B\) picks up the remaining card. Each p...
[ "dp[0][2n-1]" ]
[ "Two players, \\(A\\) and \\(B\\), play a game with \\(2n\\) cards. Each card has a positive integer written on it. The cards are shuffled and laid out in a row with the numbers facing upwards. \\(A\\) starts and the players take turns to remove one card from either end of the row until \\(B\\) picks up the remaini...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect" ]
{ "cot": 3, "genselect": 6 }
9
0
0
omr-ws-273e54d37fc004a36b699972144eff5c8a41c4488f2cfeafe5dfe6a6373719e5
Two players, \(A\) and \(B\), play a game with seven cards numbered \(1, 2, 3, 4, 5, 6, 7\). Player \(A\) picks a card first, writes the number on the card down, and returns it to the deck. If the sum of the numbers written is a multiple of 3, the game ends and the player who went last wins. Compute the probability tha...
[ "\\(\\frac{43}{75}\\)" ]
[ "Two players, \\(A\\) and \\(B\\), play a game with seven cards numbered \\(1, 2, 3, 4, 5, 6, 7\\). Player \\(A\\) picks a card first, writes the number on the card down, and returns it to the deck. If the sum of the numbers written is a multiple of 3, the game ends and the player who went last wins. Compute the pr...
[ "aops_c4_high_school_math", "c4_high_school_math" ]
[ "cot", "genselect", "tir" ]
{ "cot": 13, "genselect": 7, "tir": 23 }
43
0
0
omr-ws-a0b222f099a8d6c5f0125047867541e4a23a88ba336593da98a8c1ef2467931d
Two players, \(A\) and \(B\), play a game. At the beginning there is the number \(2\). \(A\) goes first. In each turn, the player chooses a proper divisor of the current number, and adds it to the current number. The first player who, after his/her turn, makes the number exceed a certain integer \(k\), loses. Suppose t...
[ "A wins for both \\( k = 2011^{2011} \\) and \\( k = 2012^{2012} \\)." ]
[ "Two players, \\(A\\) and \\(B\\), play a game. At the beginning there is the number \\(2\\). \\(A\\) goes first. In each turn, the player chooses a proper divisor of the current number, and adds it to the current number. The first player who, after his/her turn, makes the number exceed a certain integer \\(k\\), l...
[ "aops_c5_contests_amp_programs" ]
[ "cot", "tir" ]
{ "cot": 7, "tir": 11 }
18
0
0