message stringlengths 2 28.7k | message_type stringclasses 2 values | message_id int64 0 1 | conversation_id int64 21 109k | cluster float64 7 7 | __index_level_0__ int64 42 217k |
|---|---|---|---|---|---|
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
We have N colored balls arranged in a row from left to right; the color of the i-th ball from the left is c_i.
You are given Q queries. The i-th query is as follows: how many different colors do the l_i-th through r_i-th balls from the left have?
Constraints
* 1\leq N,Q \leq 5 \times 10^5
* 1\leq c_i \leq N
* 1\leq l_i \leq r_i \leq N
* All values in input are integers.
Input
Input is given from Standard Input in the following format:
N Q
c_1 c_2 \cdots c_N
l_1 r_1
l_2 r_2
:
l_Q r_Q
Output
Print Q lines. The i-th line should contain the response to the i-th query.
Examples
Input
4 3
1 2 1 3
1 3
2 4
3 3
Output
2
3
1
Input
10 10
2 5 6 5 2 1 7 9 7 2
5 5
2 4
6 7
2 2
7 8
7 9
1 8
6 9
8 10
6 8
Output
1
2
2
1
2
2
6
3
3
3
Submitted Solution:
```
import sys
input = sys.stdin.buffer.readline
N,Q = map(int,input().split())
BIT = [0]*(N+1)
def BIT_query(idx):
res_sum = 0
while idx > 0:
res_sum += BIT[idx]
idx -= idx&(-idx)
return res_sum
def BIT_update(idx,x):
while idx <= N:
BIT[idx] += x
idx += idx&(-idx)
return
c = [0]+list(map(int,input().split()))
lastAppeared = [-1]*(N+1)
ans = [0]*Q
queries = []
for q in range(Q):
l,r = map(int,input().split())
queries.append(r*10**12+l*10**6+q)
queries.sort()
curR = 0
for i in range(Q):
query = queries[i]
r = query//10**12
l = (query//10**6)%(10**6)
q = query % 10**6
while curR < r:
curR += 1
color = c[curR]
last = lastAppeared[color]
if last != -1:
BIT_update(last,-1)
lastAppeared[color] = curR
BIT_update(curR,1)
ans[q] = BIT_query(r)-BIT_query(l-1)
for i in range(Q):
print(ans[i])
``` | instruction | 0 | 6,373 | 7 | 12,746 |
Yes | output | 1 | 6,373 | 7 | 12,747 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
We have N colored balls arranged in a row from left to right; the color of the i-th ball from the left is c_i.
You are given Q queries. The i-th query is as follows: how many different colors do the l_i-th through r_i-th balls from the left have?
Constraints
* 1\leq N,Q \leq 5 \times 10^5
* 1\leq c_i \leq N
* 1\leq l_i \leq r_i \leq N
* All values in input are integers.
Input
Input is given from Standard Input in the following format:
N Q
c_1 c_2 \cdots c_N
l_1 r_1
l_2 r_2
:
l_Q r_Q
Output
Print Q lines. The i-th line should contain the response to the i-th query.
Examples
Input
4 3
1 2 1 3
1 3
2 4
3 3
Output
2
3
1
Input
10 10
2 5 6 5 2 1 7 9 7 2
5 5
2 4
6 7
2 2
7 8
7 9
1 8
6 9
8 10
6 8
Output
1
2
2
1
2
2
6
3
3
3
Submitted Solution:
```
import sys
input = sys.stdin.readline
class Bit:
"""1-indexed"""
def __init__(self, n):
self.size = n
self.tree = [0] * (n + 1)
def sum(self, i):
s = 0
while i > 0:
s += self.tree[i]
i -= i & -i
return s
def add(self, i, x):
while i <= self.size:
self.tree[i] += x
i += i & -i
N, Q = map(int, input().split())
C = tuple(map(int, input().split()))
queries = []
for i in range(Q):
l, r = map(int, input().split())
queries.append((l, r, i))
queries.sort(key=lambda x: x[1])
b = Bit(N)
last = [None] * (N + 1)
cur = 1
ans = [0] * Q
for l, r, i in queries:
while cur <= r:
if last[C[cur - 1]] is not None:
b.add(last[C[cur - 1]], -1)
last[C[cur - 1]] = cur
b.add(cur, 1)
cur += 1
ans[i] = b.sum(r) - b.sum(l - 1)
print(*ans, sep='\n')
``` | instruction | 0 | 6,374 | 7 | 12,748 |
Yes | output | 1 | 6,374 | 7 | 12,749 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
We have N colored balls arranged in a row from left to right; the color of the i-th ball from the left is c_i.
You are given Q queries. The i-th query is as follows: how many different colors do the l_i-th through r_i-th balls from the left have?
Constraints
* 1\leq N,Q \leq 5 \times 10^5
* 1\leq c_i \leq N
* 1\leq l_i \leq r_i \leq N
* All values in input are integers.
Input
Input is given from Standard Input in the following format:
N Q
c_1 c_2 \cdots c_N
l_1 r_1
l_2 r_2
:
l_Q r_Q
Output
Print Q lines. The i-th line should contain the response to the i-th query.
Examples
Input
4 3
1 2 1 3
1 3
2 4
3 3
Output
2
3
1
Input
10 10
2 5 6 5 2 1 7 9 7 2
5 5
2 4
6 7
2 2
7 8
7 9
1 8
6 9
8 10
6 8
Output
1
2
2
1
2
2
6
3
3
3
Submitted Solution:
```
#!usr/bin/env python3
import sys
def LI(): return [int(x) for x in sys.stdin.readline().split()]
def LIR(n):
return [[i,LI()] for i in range(n)]
def solve():
def add(i,x):
while i < len(bit):
bit[i] += x
i += i&-i
def sum_(i):
res = 0
while i > 0:
res += bit[i]
i -= i&-i
return res
n,Q = LI()
c = LI()
c = [0]+c
q = LIR(Q)
q.sort(key = lambda x:x[1][1])
bit = [0]*(n+2)
i = 1
p = [None]*(n+1)
ans = [0]*Q
s = 0
for ind,(l, r) in q:
l -= 1
while i <= r:
ci = c[i]
j = p[ci]
if j is not None:
add(j,1)
else:
s += 1
p[ci] = i
i += 1
ans[ind] = s-l+sum_(l)
for i in ans:
print(i)
return
#Solve
if __name__ == "__main__":
solve()
``` | instruction | 0 | 6,375 | 7 | 12,750 |
Yes | output | 1 | 6,375 | 7 | 12,751 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
We have N colored balls arranged in a row from left to right; the color of the i-th ball from the left is c_i.
You are given Q queries. The i-th query is as follows: how many different colors do the l_i-th through r_i-th balls from the left have?
Constraints
* 1\leq N,Q \leq 5 \times 10^5
* 1\leq c_i \leq N
* 1\leq l_i \leq r_i \leq N
* All values in input are integers.
Input
Input is given from Standard Input in the following format:
N Q
c_1 c_2 \cdots c_N
l_1 r_1
l_2 r_2
:
l_Q r_Q
Output
Print Q lines. The i-th line should contain the response to the i-th query.
Examples
Input
4 3
1 2 1 3
1 3
2 4
3 3
Output
2
3
1
Input
10 10
2 5 6 5 2 1 7 9 7 2
5 5
2 4
6 7
2 2
7 8
7 9
1 8
6 9
8 10
6 8
Output
1
2
2
1
2
2
6
3
3
3
Submitted Solution:
```
import sys
input=sys.stdin.readline
n,q=map(int,input().split())
c=list(map(int,input().split()))
l=[]
for i in range(q):
L,R=map(int,input().split())
l.append([L,R,i])
l.sort(key=lambda x:x[1])
L=[-1]*(5*10**5+1)
class Bit:
def __init__(self,n):
self.size=n
self.tree=[0]*(n + 1)
self.depth=n.bit_length()
def sum(self,i):
s=0
while i>0:
s+=self.tree[i]
i-=i&-i
return s
def add(self,i,x):
while i<=self.size:
self.tree[i]+=x
i+=i&-i
BIT=Bit(n+1)
ans=[0]*q
ct=0
for i in range(q):
while ct<=l[i][1]:
if L[c[ct-1]-1]!=-1:
BIT.add(L[c[ct-1]-1],-1)
L[c[ct-1]-1]=ct+1
BIT.add(ct+1,1)
ct+=1
ans[l[i][2]]=BIT.sum(l[i][1]+1)-BIT.sum(l[i][0])
for i in range(q):
print(ans[i])
``` | instruction | 0 | 6,376 | 7 | 12,752 |
Yes | output | 1 | 6,376 | 7 | 12,753 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
We have N colored balls arranged in a row from left to right; the color of the i-th ball from the left is c_i.
You are given Q queries. The i-th query is as follows: how many different colors do the l_i-th through r_i-th balls from the left have?
Constraints
* 1\leq N,Q \leq 5 \times 10^5
* 1\leq c_i \leq N
* 1\leq l_i \leq r_i \leq N
* All values in input are integers.
Input
Input is given from Standard Input in the following format:
N Q
c_1 c_2 \cdots c_N
l_1 r_1
l_2 r_2
:
l_Q r_Q
Output
Print Q lines. The i-th line should contain the response to the i-th query.
Examples
Input
4 3
1 2 1 3
1 3
2 4
3 3
Output
2
3
1
Input
10 10
2 5 6 5 2 1 7 9 7 2
5 5
2 4
6 7
2 2
7 8
7 9
1 8
6 9
8 10
6 8
Output
1
2
2
1
2
2
6
3
3
3
Submitted Solution:
```
def segfunc(x,y):
return x|y
ide_ele=set()
class SegTree():
def __init__(self,init_val,segfunc,ide_ele):
n=len(init_val)
self.segfunc=segfunc
self.ide_ele=ide_ele
self.num=1<<(n-1).bit_length()
self.tree=[ide_ele]*2*self.num
for i in range(n):
self.tree[self.num+i]={init_val[i]}
for i in range(self.num-1,0,-1):
self.tree[i]=self.segfunc(self.tree[2*i], self.tree[2*i+1])
def update(self,k,x):
k+=self.num
self.tree[k]=x
while k>1:
self.tree[k>>1]=self.segfunc(self.tree[k],self.tree[k^1])
k>>=1
def query(self,l,r):
res=self.ide_ele
l+=self.num
r+=self.num
while l<r:
if l&1:
res=self.segfunc(res,self.tree[l])
l+=1
if r&1:
res=self.segfunc(res,self.tree[r-1])
l>>=1
r>>=1
return res
n,q=map(int,input().split())
c=list(map(int,input().split()))
st=SegTree(c,segfunc,ide_ele)
for _ in range(q):
l,r=map(int,input().split())
print(len(st.query(l-1,r)))
``` | instruction | 0 | 6,377 | 7 | 12,754 |
No | output | 1 | 6,377 | 7 | 12,755 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
We have N colored balls arranged in a row from left to right; the color of the i-th ball from the left is c_i.
You are given Q queries. The i-th query is as follows: how many different colors do the l_i-th through r_i-th balls from the left have?
Constraints
* 1\leq N,Q \leq 5 \times 10^5
* 1\leq c_i \leq N
* 1\leq l_i \leq r_i \leq N
* All values in input are integers.
Input
Input is given from Standard Input in the following format:
N Q
c_1 c_2 \cdots c_N
l_1 r_1
l_2 r_2
:
l_Q r_Q
Output
Print Q lines. The i-th line should contain the response to the i-th query.
Examples
Input
4 3
1 2 1 3
1 3
2 4
3 3
Output
2
3
1
Input
10 10
2 5 6 5 2 1 7 9 7 2
5 5
2 4
6 7
2 2
7 8
7 9
1 8
6 9
8 10
6 8
Output
1
2
2
1
2
2
6
3
3
3
Submitted Solution:
```
def main():
n,q=map(int,input().split())
lst=[0]*n
clst=tuple(map(int,input().split()))
work={}
for i in range(n):
if clst[i] in work:
work[clst[i]]+=1
else :
work[clst[i]]=1
lst[i]=work.copy()
for _ in range(q):
l,r=map(int,input().split())
rwork=lst[r-1]
if l==1 :
print(len(rwork))
continue
lwork=lst[l-2]
sm=len(rwork)
for x in rwork:
if x not in lwork : continue
if rwork[x]==lwork[x]:
sm-=1
print(sm)
main()
``` | instruction | 0 | 6,378 | 7 | 12,756 |
No | output | 1 | 6,378 | 7 | 12,757 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
We have N colored balls arranged in a row from left to right; the color of the i-th ball from the left is c_i.
You are given Q queries. The i-th query is as follows: how many different colors do the l_i-th through r_i-th balls from the left have?
Constraints
* 1\leq N,Q \leq 5 \times 10^5
* 1\leq c_i \leq N
* 1\leq l_i \leq r_i \leq N
* All values in input are integers.
Input
Input is given from Standard Input in the following format:
N Q
c_1 c_2 \cdots c_N
l_1 r_1
l_2 r_2
:
l_Q r_Q
Output
Print Q lines. The i-th line should contain the response to the i-th query.
Examples
Input
4 3
1 2 1 3
1 3
2 4
3 3
Output
2
3
1
Input
10 10
2 5 6 5 2 1 7 9 7 2
5 5
2 4
6 7
2 2
7 8
7 9
1 8
6 9
8 10
6 8
Output
1
2
2
1
2
2
6
3
3
3
Submitted Solution:
```
import sys
from operator import itemgetter
buf = sys.stdin.buffer
input = buf.readline
class BIT:
def __init__(self, n):
self.n = n
self.tree = [0] * (n + 1)
def add(self, i, x):
n, tree = self.n, self.tree
while i <= n:
tree[i] += x
i += i & -i
def sum(self, i):
tree = self.tree
s = 0
while i:
s += tree[i]
i -= i & -i
return s
def main():
n, q = map(int, input().split())
res = [0] * q
*c, = map(int, input().split())
q = [(i, l, r) for i, (l, r) in enumerate(zip(*[map(int, buf.read().split())] * 2))]
q.sort(key=itemgetter(2))
bit = BIT(n + 2)
add, sum = bit.add, bit.sum
b = [1] * (n + 1)
j = 1
for i, l, r in q:
while j <= r:
d = c[j - 1]
j += 1
k = b[d]
b[d] = j
add(k + 1, 1)
add(j + 1, -1)
res[i] = sum(l + 1)
print(' '.join(map(str, res)))
main()
``` | instruction | 0 | 6,379 | 7 | 12,758 |
No | output | 1 | 6,379 | 7 | 12,759 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
We have N colored balls arranged in a row from left to right; the color of the i-th ball from the left is c_i.
You are given Q queries. The i-th query is as follows: how many different colors do the l_i-th through r_i-th balls from the left have?
Constraints
* 1\leq N,Q \leq 5 \times 10^5
* 1\leq c_i \leq N
* 1\leq l_i \leq r_i \leq N
* All values in input are integers.
Input
Input is given from Standard Input in the following format:
N Q
c_1 c_2 \cdots c_N
l_1 r_1
l_2 r_2
:
l_Q r_Q
Output
Print Q lines. The i-th line should contain the response to the i-th query.
Examples
Input
4 3
1 2 1 3
1 3
2 4
3 3
Output
2
3
1
Input
10 10
2 5 6 5 2 1 7 9 7 2
5 5
2 4
6 7
2 2
7 8
7 9
1 8
6 9
8 10
6 8
Output
1
2
2
1
2
2
6
3
3
3
Submitted Solution:
```
import bisect
def answer(kintama, lri0):
tama = kintama[:]
tama.sort()
num = bisect.bisect_left(tama, lri0)
return 10**5+1 - num
n, q = [int(i) for i in input().split()]
c = [int(i)-1 for i in input().split()]
lr = []
for i in range(q):
lr_ = [int(_)-1 for _ in input().split()] + [i]
lr.append(lr_)
lr.sort(key=lambda x: x[1])
k = 0
ans = []
kintama = [-10 for i in range(10**5+1)]
for i in range(q):
while lr[i][1] > k:
kintama[c[k]] = k
k += 1
kintama[c[k]] = k
ans.append([answer(kintama, lr[i][0]), lr[i][2]])
ans.sort(key=lambda x: x[1])
[print(ans[i][0]) for i in range(q)]
``` | instruction | 0 | 6,380 | 7 | 12,760 |
No | output | 1 | 6,380 | 7 | 12,761 |
Provide a correct Python 3 solution for this coding contest problem.
We have an N \times N square grid.
We will paint each square in the grid either black or white.
If we paint exactly A squares white, how many squares will be painted black?
Constraints
* 1 \leq N \leq 100
* 0 \leq A \leq N^2
Inputs
Input is given from Standard Input in the following format:
N
A
Outputs
Print the number of squares that will be painted black.
Examples
Input
3
4
Output
5
Input
19
100
Output
261
Input
10
0
Output
100 | instruction | 0 | 6,477 | 7 | 12,954 |
"Correct Solution:
```
import math
n=int(input())
a=int(input())
print(n*n-a)
``` | output | 1 | 6,477 | 7 | 12,955 |
Provide a correct Python 3 solution for this coding contest problem.
We have an N \times N square grid.
We will paint each square in the grid either black or white.
If we paint exactly A squares white, how many squares will be painted black?
Constraints
* 1 \leq N \leq 100
* 0 \leq A \leq N^2
Inputs
Input is given from Standard Input in the following format:
N
A
Outputs
Print the number of squares that will be painted black.
Examples
Input
3
4
Output
5
Input
19
100
Output
261
Input
10
0
Output
100 | instruction | 0 | 6,478 | 7 | 12,956 |
"Correct Solution:
```
x=int(input())
y=int(input())
print(x*x-y)
``` | output | 1 | 6,478 | 7 | 12,957 |
Provide a correct Python 3 solution for this coding contest problem.
We have an N \times N square grid.
We will paint each square in the grid either black or white.
If we paint exactly A squares white, how many squares will be painted black?
Constraints
* 1 \leq N \leq 100
* 0 \leq A \leq N^2
Inputs
Input is given from Standard Input in the following format:
N
A
Outputs
Print the number of squares that will be painted black.
Examples
Input
3
4
Output
5
Input
19
100
Output
261
Input
10
0
Output
100 | instruction | 0 | 6,479 | 7 | 12,958 |
"Correct Solution:
```
#coding: utf-8
print(int(input())**2 - int(input()))
``` | output | 1 | 6,479 | 7 | 12,959 |
Provide a correct Python 3 solution for this coding contest problem.
We have an N \times N square grid.
We will paint each square in the grid either black or white.
If we paint exactly A squares white, how many squares will be painted black?
Constraints
* 1 \leq N \leq 100
* 0 \leq A \leq N^2
Inputs
Input is given from Standard Input in the following format:
N
A
Outputs
Print the number of squares that will be painted black.
Examples
Input
3
4
Output
5
Input
19
100
Output
261
Input
10
0
Output
100 | instruction | 0 | 6,480 | 7 | 12,960 |
"Correct Solution:
```
n = int(input())
a = int(input())
x = n*n-a
print(x)
``` | output | 1 | 6,480 | 7 | 12,961 |
Provide a correct Python 3 solution for this coding contest problem.
We have an N \times N square grid.
We will paint each square in the grid either black or white.
If we paint exactly A squares white, how many squares will be painted black?
Constraints
* 1 \leq N \leq 100
* 0 \leq A \leq N^2
Inputs
Input is given from Standard Input in the following format:
N
A
Outputs
Print the number of squares that will be painted black.
Examples
Input
3
4
Output
5
Input
19
100
Output
261
Input
10
0
Output
100 | instruction | 0 | 6,481 | 7 | 12,962 |
"Correct Solution:
```
N = int(input())
A = int(input())
Y = N**2 -A
print(Y)
``` | output | 1 | 6,481 | 7 | 12,963 |
Provide a correct Python 3 solution for this coding contest problem.
We have an N \times N square grid.
We will paint each square in the grid either black or white.
If we paint exactly A squares white, how many squares will be painted black?
Constraints
* 1 \leq N \leq 100
* 0 \leq A \leq N^2
Inputs
Input is given from Standard Input in the following format:
N
A
Outputs
Print the number of squares that will be painted black.
Examples
Input
3
4
Output
5
Input
19
100
Output
261
Input
10
0
Output
100 | instruction | 0 | 6,482 | 7 | 12,964 |
"Correct Solution:
```
n=int(input())
s=int(input())
print(n*n-s)
``` | output | 1 | 6,482 | 7 | 12,965 |
Provide a correct Python 3 solution for this coding contest problem.
We have an N \times N square grid.
We will paint each square in the grid either black or white.
If we paint exactly A squares white, how many squares will be painted black?
Constraints
* 1 \leq N \leq 100
* 0 \leq A \leq N^2
Inputs
Input is given from Standard Input in the following format:
N
A
Outputs
Print the number of squares that will be painted black.
Examples
Input
3
4
Output
5
Input
19
100
Output
261
Input
10
0
Output
100 | instruction | 0 | 6,483 | 7 | 12,966 |
"Correct Solution:
```
n=int(input())
a=int(input())
n=pow(n,2)
print(n-a)
``` | output | 1 | 6,483 | 7 | 12,967 |
Provide a correct Python 3 solution for this coding contest problem.
We have an N \times N square grid.
We will paint each square in the grid either black or white.
If we paint exactly A squares white, how many squares will be painted black?
Constraints
* 1 \leq N \leq 100
* 0 \leq A \leq N^2
Inputs
Input is given from Standard Input in the following format:
N
A
Outputs
Print the number of squares that will be painted black.
Examples
Input
3
4
Output
5
Input
19
100
Output
261
Input
10
0
Output
100 | instruction | 0 | 6,484 | 7 | 12,968 |
"Correct Solution:
```
n=input()
x=int(input())
m=int(n)*int(n)
print(m-x)
``` | output | 1 | 6,484 | 7 | 12,969 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
We have an N \times N square grid.
We will paint each square in the grid either black or white.
If we paint exactly A squares white, how many squares will be painted black?
Constraints
* 1 \leq N \leq 100
* 0 \leq A \leq N^2
Inputs
Input is given from Standard Input in the following format:
N
A
Outputs
Print the number of squares that will be painted black.
Examples
Input
3
4
Output
5
Input
19
100
Output
261
Input
10
0
Output
100
Submitted Solution:
```
#10:40
n = int(input())
a = int(input())
print ( n * n - a )
``` | instruction | 0 | 6,485 | 7 | 12,970 |
Yes | output | 1 | 6,485 | 7 | 12,971 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
We have an N \times N square grid.
We will paint each square in the grid either black or white.
If we paint exactly A squares white, how many squares will be painted black?
Constraints
* 1 \leq N \leq 100
* 0 \leq A \leq N^2
Inputs
Input is given from Standard Input in the following format:
N
A
Outputs
Print the number of squares that will be painted black.
Examples
Input
3
4
Output
5
Input
19
100
Output
261
Input
10
0
Output
100
Submitted Solution:
```
n = int(input())
A = int(input())
print(n*n - A)
``` | instruction | 0 | 6,486 | 7 | 12,972 |
Yes | output | 1 | 6,486 | 7 | 12,973 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
We have an N \times N square grid.
We will paint each square in the grid either black or white.
If we paint exactly A squares white, how many squares will be painted black?
Constraints
* 1 \leq N \leq 100
* 0 \leq A \leq N^2
Inputs
Input is given from Standard Input in the following format:
N
A
Outputs
Print the number of squares that will be painted black.
Examples
Input
3
4
Output
5
Input
19
100
Output
261
Input
10
0
Output
100
Submitted Solution:
```
n = int(input())
a = int(input())
print(int((n*n) - a))
``` | instruction | 0 | 6,487 | 7 | 12,974 |
Yes | output | 1 | 6,487 | 7 | 12,975 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
We have an N \times N square grid.
We will paint each square in the grid either black or white.
If we paint exactly A squares white, how many squares will be painted black?
Constraints
* 1 \leq N \leq 100
* 0 \leq A \leq N^2
Inputs
Input is given from Standard Input in the following format:
N
A
Outputs
Print the number of squares that will be painted black.
Examples
Input
3
4
Output
5
Input
19
100
Output
261
Input
10
0
Output
100
Submitted Solution:
```
N = int(input()) ** 2
A = int(input())
print(str(N - A))
``` | instruction | 0 | 6,488 | 7 | 12,976 |
Yes | output | 1 | 6,488 | 7 | 12,977 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
We have an N \times N square grid.
We will paint each square in the grid either black or white.
If we paint exactly A squares white, how many squares will be painted black?
Constraints
* 1 \leq N \leq 100
* 0 \leq A \leq N^2
Inputs
Input is given from Standard Input in the following format:
N
A
Outputs
Print the number of squares that will be painted black.
Examples
Input
3
4
Output
5
Input
19
100
Output
261
Input
10
0
Output
100
Submitted Solution:
```
N,A=map(int,input().split())
print((N*N)-A)
``` | instruction | 0 | 6,489 | 7 | 12,978 |
No | output | 1 | 6,489 | 7 | 12,979 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
We have an N \times N square grid.
We will paint each square in the grid either black or white.
If we paint exactly A squares white, how many squares will be painted black?
Constraints
* 1 \leq N \leq 100
* 0 \leq A \leq N^2
Inputs
Input is given from Standard Input in the following format:
N
A
Outputs
Print the number of squares that will be painted black.
Examples
Input
3
4
Output
5
Input
19
100
Output
261
Input
10
0
Output
100
Submitted Solution:
```
#from numpy import*
from scipy.sparse.csgraph import shortest_path #shortest_path(csgraph=graph)
#from scipy.sparse.csgraph import dijkstra
from scipy.sparse import csr_matrix
from collections import* #defaultdict Counter deque appendleft
from fractions import gcd
from functools import* #reduce
from itertools import* #permutations("AB",repeat=2) combinations("AB",2) product("AB",2) groupby accumulate
from operator import mul,itemgetter
from bisect import* #bisect_left bisect_right
from heapq import* #heapify heappop heappushpop
from math import factorial,pi
from copy import deepcopy
import sys
#input=sys.stdin.readline #ε±ιΊοΌεΊζ¬γͺγγ«γγοΌ
sys.setrecursionlimit(10**8)
def main():
n=int(input())
grid=[list(map(int,input().split()))for i in range(n)]
p=shortest_path(csgraph=csr_matrix(grid))
q=[list(i) for i in p]
if q!=grid:
print(-1)
else:
for i in range(n):
p[i][i]=float("inf")
ans=0
P=[min(p[i])for i in range(n)]
# print(p)
for i in range(n):
for j in range(i):
if i==j:
continue
if p[i][j]<P[i]+P[j]:
ans+=p[i][j]
print(int(ans))
``` | instruction | 0 | 6,490 | 7 | 12,980 |
No | output | 1 | 6,490 | 7 | 12,981 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
We have an N \times N square grid.
We will paint each square in the grid either black or white.
If we paint exactly A squares white, how many squares will be painted black?
Constraints
* 1 \leq N \leq 100
* 0 \leq A \leq N^2
Inputs
Input is given from Standard Input in the following format:
N
A
Outputs
Print the number of squares that will be painted black.
Examples
Input
3
4
Output
5
Input
19
100
Output
261
Input
10
0
Output
100
Submitted Solution:
```
a=int(input())
b=int(input())
print(a^2-b)
``` | instruction | 0 | 6,491 | 7 | 12,982 |
No | output | 1 | 6,491 | 7 | 12,983 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
We have an N \times N square grid.
We will paint each square in the grid either black or white.
If we paint exactly A squares white, how many squares will be painted black?
Constraints
* 1 \leq N \leq 100
* 0 \leq A \leq N^2
Inputs
Input is given from Standard Input in the following format:
N
A
Outputs
Print the number of squares that will be painted black.
Examples
Input
3
4
Output
5
Input
19
100
Output
261
Input
10
0
Output
100
Submitted Solution:
```
a = input()
n = input()
a = int(a)
n = int(n)
print (n * n - a)
``` | instruction | 0 | 6,492 | 7 | 12,984 |
No | output | 1 | 6,492 | 7 | 12,985 |
Provide tags and a correct Python 2 solution for this coding contest problem.
Kyoya Ootori has a bag with n colored balls that are colored with k different colors. The colors are labeled from 1 to k. Balls of the same color are indistinguishable. He draws balls from the bag one by one until the bag is empty. He noticed that he drew the last ball of color i before drawing the last ball of color i + 1 for all i from 1 to k - 1. Now he wonders how many different ways this can happen.
Input
The first line of input will have one integer k (1 β€ k β€ 1000) the number of colors.
Then, k lines will follow. The i-th line will contain ci, the number of balls of the i-th color (1 β€ ci β€ 1000).
The total number of balls doesn't exceed 1000.
Output
A single integer, the number of ways that Kyoya can draw the balls from the bag as described in the statement, modulo 1 000 000 007.
Examples
Input
3
2
2
1
Output
3
Input
4
1
2
3
4
Output
1680
Note
In the first sample, we have 2 balls of color 1, 2 balls of color 2, and 1 ball of color 3. The three ways for Kyoya are:
1 2 1 2 3
1 1 2 2 3
2 1 1 2 3
| instruction | 0 | 7,078 | 7 | 14,156 |
Tags: combinatorics, dp, math
Correct Solution:
```
# File: o (Python 3.4)
#045c8f47ec44c634
import math
n = input()
wow = 0
ans = 1
mod = 1000000007
for i in range(0,n):
tmp = input()
if (i == 0):
wow = wow + tmp
else:
ans = ans * math.factorial(wow + tmp - 1)/math.factorial(wow)
'''for j in range(1, tmp):
wow = wow + 1
ans = (ans * wow) % mod'''
ans = ans/math.factorial(tmp - 1) % mod
wow = wow + tmp
print ans
``` | output | 1 | 7,078 | 7 | 14,157 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Kyoya Ootori has a bag with n colored balls that are colored with k different colors. The colors are labeled from 1 to k. Balls of the same color are indistinguishable. He draws balls from the bag one by one until the bag is empty. He noticed that he drew the last ball of color i before drawing the last ball of color i + 1 for all i from 1 to k - 1. Now he wonders how many different ways this can happen.
Input
The first line of input will have one integer k (1 β€ k β€ 1000) the number of colors.
Then, k lines will follow. The i-th line will contain ci, the number of balls of the i-th color (1 β€ ci β€ 1000).
The total number of balls doesn't exceed 1000.
Output
A single integer, the number of ways that Kyoya can draw the balls from the bag as described in the statement, modulo 1 000 000 007.
Examples
Input
3
2
2
1
Output
3
Input
4
1
2
3
4
Output
1680
Note
In the first sample, we have 2 balls of color 1, 2 balls of color 2, and 1 ball of color 3. The three ways for Kyoya are:
1 2 1 2 3
1 1 2 2 3
2 1 1 2 3
| instruction | 0 | 7,079 | 7 | 14,158 |
Tags: combinatorics, dp, math
Correct Solution:
```
def c(k,l):
d=1
for i in range(k+1,l+k+1): d*=i
for i in range(l): d//=(i+1)
return d%1000000007
ans=1
n=int(input())
k=int(input())
for t in range(1,n):
a=int(input())
ans*=c(k,a-1)%1000000007
k+=a
print(ans%1000000007)
``` | output | 1 | 7,079 | 7 | 14,159 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Kyoya Ootori has a bag with n colored balls that are colored with k different colors. The colors are labeled from 1 to k. Balls of the same color are indistinguishable. He draws balls from the bag one by one until the bag is empty. He noticed that he drew the last ball of color i before drawing the last ball of color i + 1 for all i from 1 to k - 1. Now he wonders how many different ways this can happen.
Input
The first line of input will have one integer k (1 β€ k β€ 1000) the number of colors.
Then, k lines will follow. The i-th line will contain ci, the number of balls of the i-th color (1 β€ ci β€ 1000).
The total number of balls doesn't exceed 1000.
Output
A single integer, the number of ways that Kyoya can draw the balls from the bag as described in the statement, modulo 1 000 000 007.
Examples
Input
3
2
2
1
Output
3
Input
4
1
2
3
4
Output
1680
Note
In the first sample, we have 2 balls of color 1, 2 balls of color 2, and 1 ball of color 3. The three ways for Kyoya are:
1 2 1 2 3
1 1 2 2 3
2 1 1 2 3
| instruction | 0 | 7,080 | 7 | 14,160 |
Tags: combinatorics, dp, math
Correct Solution:
```
from math import factorial
n,ans,s = int(input()),1,0
for i in range(n) :
a = int(input())
ans=(ans*factorial(s+a-1)//factorial(s)//factorial(a-1))%1000000007
s+=a
print(ans)
#copied...
# Made By Mostafa_Khaled
``` | output | 1 | 7,080 | 7 | 14,161 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Kyoya Ootori has a bag with n colored balls that are colored with k different colors. The colors are labeled from 1 to k. Balls of the same color are indistinguishable. He draws balls from the bag one by one until the bag is empty. He noticed that he drew the last ball of color i before drawing the last ball of color i + 1 for all i from 1 to k - 1. Now he wonders how many different ways this can happen.
Input
The first line of input will have one integer k (1 β€ k β€ 1000) the number of colors.
Then, k lines will follow. The i-th line will contain ci, the number of balls of the i-th color (1 β€ ci β€ 1000).
The total number of balls doesn't exceed 1000.
Output
A single integer, the number of ways that Kyoya can draw the balls from the bag as described in the statement, modulo 1 000 000 007.
Examples
Input
3
2
2
1
Output
3
Input
4
1
2
3
4
Output
1680
Note
In the first sample, we have 2 balls of color 1, 2 balls of color 2, and 1 ball of color 3. The three ways for Kyoya are:
1 2 1 2 3
1 1 2 2 3
2 1 1 2 3
| instruction | 0 | 7,081 | 7 | 14,162 |
Tags: combinatorics, dp, math
Correct Solution:
```
from math import factorial as f
n=int(input())
d=0
out=1
for i in range(n) :
m=int(input())
out=out*f(d+m-1)//f(d)//f(m-1)%1000000007
d+=m
print(out)
``` | output | 1 | 7,081 | 7 | 14,163 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Kyoya Ootori has a bag with n colored balls that are colored with k different colors. The colors are labeled from 1 to k. Balls of the same color are indistinguishable. He draws balls from the bag one by one until the bag is empty. He noticed that he drew the last ball of color i before drawing the last ball of color i + 1 for all i from 1 to k - 1. Now he wonders how many different ways this can happen.
Input
The first line of input will have one integer k (1 β€ k β€ 1000) the number of colors.
Then, k lines will follow. The i-th line will contain ci, the number of balls of the i-th color (1 β€ ci β€ 1000).
The total number of balls doesn't exceed 1000.
Output
A single integer, the number of ways that Kyoya can draw the balls from the bag as described in the statement, modulo 1 000 000 007.
Examples
Input
3
2
2
1
Output
3
Input
4
1
2
3
4
Output
1680
Note
In the first sample, we have 2 balls of color 1, 2 balls of color 2, and 1 ball of color 3. The three ways for Kyoya are:
1 2 1 2 3
1 1 2 2 3
2 1 1 2 3
| instruction | 0 | 7,082 | 7 | 14,164 |
Tags: combinatorics, dp, math
Correct Solution:
```
k = int(input())
colors = []
for i in range(k) :
colors.append(int(input()))
ans = 1
accum = colors[0]
for i in range(1, k):
for j in range(1, colors[i]):
ans *= (accum + j)
for j in range(1, colors[i]):
ans //= j
accum += colors[i]
print(ans % 1000000007)
``` | output | 1 | 7,082 | 7 | 14,165 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Kyoya Ootori has a bag with n colored balls that are colored with k different colors. The colors are labeled from 1 to k. Balls of the same color are indistinguishable. He draws balls from the bag one by one until the bag is empty. He noticed that he drew the last ball of color i before drawing the last ball of color i + 1 for all i from 1 to k - 1. Now he wonders how many different ways this can happen.
Input
The first line of input will have one integer k (1 β€ k β€ 1000) the number of colors.
Then, k lines will follow. The i-th line will contain ci, the number of balls of the i-th color (1 β€ ci β€ 1000).
The total number of balls doesn't exceed 1000.
Output
A single integer, the number of ways that Kyoya can draw the balls from the bag as described in the statement, modulo 1 000 000 007.
Examples
Input
3
2
2
1
Output
3
Input
4
1
2
3
4
Output
1680
Note
In the first sample, we have 2 balls of color 1, 2 balls of color 2, and 1 ball of color 3. The three ways for Kyoya are:
1 2 1 2 3
1 1 2 2 3
2 1 1 2 3
| instruction | 0 | 7,083 | 7 | 14,166 |
Tags: combinatorics, dp, math
Correct Solution:
```
#!/usr/bin/python3
import sys
from functools import lru_cache
MOD = 1000000007
cnk = [[1 for i in range(1001)] for j in range(1001)]
for i in range(1, 1001):
for j in range(1, i):
cnk[i][j] = cnk[i - 1][j - 1] + cnk[i - 1][j]
k = int(input())
cs = [int(input()) for i in range(k)]
ans = 1
sm = 0
for c in cs:
sm += c
ans = (ans * cnk[sm - 1][c - 1]) % MOD
print(ans)
``` | output | 1 | 7,083 | 7 | 14,167 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Kyoya Ootori has a bag with n colored balls that are colored with k different colors. The colors are labeled from 1 to k. Balls of the same color are indistinguishable. He draws balls from the bag one by one until the bag is empty. He noticed that he drew the last ball of color i before drawing the last ball of color i + 1 for all i from 1 to k - 1. Now he wonders how many different ways this can happen.
Input
The first line of input will have one integer k (1 β€ k β€ 1000) the number of colors.
Then, k lines will follow. The i-th line will contain ci, the number of balls of the i-th color (1 β€ ci β€ 1000).
The total number of balls doesn't exceed 1000.
Output
A single integer, the number of ways that Kyoya can draw the balls from the bag as described in the statement, modulo 1 000 000 007.
Examples
Input
3
2
2
1
Output
3
Input
4
1
2
3
4
Output
1680
Note
In the first sample, we have 2 balls of color 1, 2 balls of color 2, and 1 ball of color 3. The three ways for Kyoya are:
1 2 1 2 3
1 1 2 2 3
2 1 1 2 3
| instruction | 0 | 7,084 | 7 | 14,168 |
Tags: combinatorics, dp, math
Correct Solution:
```
from math import exp
def pfold (arr):
return arr[0] * pfold (arr[1:]) if arr else 1
def pscan (x, arr):
arr = (pscan (x * arr[-1], arr[:-1]) if arr else [])
arr.append(x)
return arr
def P(n, r):
return pfold(range(n, n-r, -1))
def F(n):
return P(n, n)
#return reduce(op.mul, range(n, 0, -1), 1)
def C(n, r):
if (r > n): return 0
r = min(r, n-r)
return P(n, r)//F(r)
def AC(a, b):
return C(a+b-1, b-1)
def CCC(n, k):
return AC(n, k)/F(k)
def Cat(n):
return C(2*n,n+1)/n
def Cat2(n):
return
def dot(a,b):
return sum(i*j for i, j in zip(a,b))
def Catray(n):
arr = [1]
for i in range(1,n):
arr = arr + [dot(arr,arr[::-1])]
return arr
# binomial distribution:
# with an event E which has probability p of occuring every try,
# what is the chance of E occuring exactly k times from n tries
def Bd (n, p, k):
return C(n,k)*p**k*(1-p)**(n-k)
# evaluate the sum of the binomial distribution in the range [0, k]
def BdS (n, p, k):
return sum(Bd(n, p, i) for i in range(k+1))
def Normal (mu, sigma, k):
return 0
# exponential distribution
def Ed (p, k):
return (1-p)*p**(k-1)
def EdS (p, k):
return 1 - p**k
def Pd (x, k):
return x**k/F(k) * exp(-x)
def PdS (x, k):
return (sum(pscan (1, [x/i for i in range (k, 0, -1)]))) * exp(-x)
#def PPP(n, k, m):
def nTermsSumToXInRangeAToB(n, x, a, b): # a <= b
x -= a*n
b -= a
if x < 0 or x > b*n:
return 0
else:
return nTermsUnderASumToX(n, x, b+1, 0)
def nTermsUnderASumToX(n, x, a, b):
if x < 0:
return 0
else:
return AC(x,n) - (n-b)*nTermsUnderASumToX(n, x-a, a, b+1)
def f(n, x, a, b):
return nTermsSumToXInRangeAToB(n, x, a, b)
M = 10**9+7
k = int(input())
v = 1
n = 0
for _ in range(k):
c = int(input())
v *= C(n+c-1,c-1)
v %= M
n+= c
print(v)
``` | output | 1 | 7,084 | 7 | 14,169 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Kyoya Ootori has a bag with n colored balls that are colored with k different colors. The colors are labeled from 1 to k. Balls of the same color are indistinguishable. He draws balls from the bag one by one until the bag is empty. He noticed that he drew the last ball of color i before drawing the last ball of color i + 1 for all i from 1 to k - 1. Now he wonders how many different ways this can happen.
Input
The first line of input will have one integer k (1 β€ k β€ 1000) the number of colors.
Then, k lines will follow. The i-th line will contain ci, the number of balls of the i-th color (1 β€ ci β€ 1000).
The total number of balls doesn't exceed 1000.
Output
A single integer, the number of ways that Kyoya can draw the balls from the bag as described in the statement, modulo 1 000 000 007.
Examples
Input
3
2
2
1
Output
3
Input
4
1
2
3
4
Output
1680
Note
In the first sample, we have 2 balls of color 1, 2 balls of color 2, and 1 ball of color 3. The three ways for Kyoya are:
1 2 1 2 3
1 1 2 2 3
2 1 1 2 3
| instruction | 0 | 7,085 | 7 | 14,170 |
Tags: combinatorics, dp, math
Correct Solution:
```
def binomialCoefficient(n, k):
if(k > n - k):
k = n - k
res = 1
for i in range(k):
res = res * (n - i)
res = res // (i + 1)
return res
k=int(input())
sum=0
ans=1
m=1000000007
for i in range(k):
a=int(input())
ans=(ans%m)*(binomialCoefficient(sum+a-1,a-1))%m
sum+=a
print(ans)
``` | output | 1 | 7,085 | 7 | 14,171 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Kyoya Ootori has a bag with n colored balls that are colored with k different colors. The colors are labeled from 1 to k. Balls of the same color are indistinguishable. He draws balls from the bag one by one until the bag is empty. He noticed that he drew the last ball of color i before drawing the last ball of color i + 1 for all i from 1 to k - 1. Now he wonders how many different ways this can happen.
Input
The first line of input will have one integer k (1 β€ k β€ 1000) the number of colors.
Then, k lines will follow. The i-th line will contain ci, the number of balls of the i-th color (1 β€ ci β€ 1000).
The total number of balls doesn't exceed 1000.
Output
A single integer, the number of ways that Kyoya can draw the balls from the bag as described in the statement, modulo 1 000 000 007.
Examples
Input
3
2
2
1
Output
3
Input
4
1
2
3
4
Output
1680
Note
In the first sample, we have 2 balls of color 1, 2 balls of color 2, and 1 ball of color 3. The three ways for Kyoya are:
1 2 1 2 3
1 1 2 2 3
2 1 1 2 3
| instruction | 0 | 7,086 | 7 | 14,172 |
Tags: combinatorics, dp, math
Correct Solution:
```
n = int(input())
balls = []
for i in range (n):
balls.append(int(input()))
ans = 1
urns = balls[0] + 1
def theorem(n, k): # n urns k balls
ret = 1
for i in range(1, k+1):
ret = ret * (n+k-i)
for i in range(1, k+1):
ret = ret // i
return ret
for i in range (1, n):
ans *= theorem(urns, balls[i]-1) % 1000000007
urns += balls[i]
print (ans % 1000000007)
``` | output | 1 | 7,086 | 7 | 14,173 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Kyoya Ootori has a bag with n colored balls that are colored with k different colors. The colors are labeled from 1 to k. Balls of the same color are indistinguishable. He draws balls from the bag one by one until the bag is empty. He noticed that he drew the last ball of color i before drawing the last ball of color i + 1 for all i from 1 to k - 1. Now he wonders how many different ways this can happen.
Input
The first line of input will have one integer k (1 β€ k β€ 1000) the number of colors.
Then, k lines will follow. The i-th line will contain ci, the number of balls of the i-th color (1 β€ ci β€ 1000).
The total number of balls doesn't exceed 1000.
Output
A single integer, the number of ways that Kyoya can draw the balls from the bag as described in the statement, modulo 1 000 000 007.
Examples
Input
3
2
2
1
Output
3
Input
4
1
2
3
4
Output
1680
Note
In the first sample, we have 2 balls of color 1, 2 balls of color 2, and 1 ball of color 3. The three ways for Kyoya are:
1 2 1 2 3
1 1 2 2 3
2 1 1 2 3
Submitted Solution:
```
t = int(input())
c = 1
s = int(input())
for _ in range(t-1):
n = int(input())
s += n
k = 1
for i in range(1, n):
k = k*(s-i)//i
c = (c*k) % (10**9+7)
print(c)
``` | instruction | 0 | 7,087 | 7 | 14,174 |
Yes | output | 1 | 7,087 | 7 | 14,175 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Kyoya Ootori has a bag with n colored balls that are colored with k different colors. The colors are labeled from 1 to k. Balls of the same color are indistinguishable. He draws balls from the bag one by one until the bag is empty. He noticed that he drew the last ball of color i before drawing the last ball of color i + 1 for all i from 1 to k - 1. Now he wonders how many different ways this can happen.
Input
The first line of input will have one integer k (1 β€ k β€ 1000) the number of colors.
Then, k lines will follow. The i-th line will contain ci, the number of balls of the i-th color (1 β€ ci β€ 1000).
The total number of balls doesn't exceed 1000.
Output
A single integer, the number of ways that Kyoya can draw the balls from the bag as described in the statement, modulo 1 000 000 007.
Examples
Input
3
2
2
1
Output
3
Input
4
1
2
3
4
Output
1680
Note
In the first sample, we have 2 balls of color 1, 2 balls of color 2, and 1 ball of color 3. The three ways for Kyoya are:
1 2 1 2 3
1 1 2 2 3
2 1 1 2 3
Submitted Solution:
```
# coding: utf-8
# In[6]:
matrix = [[0 for x in range(1001)] for y in range(1001)]
mod = 1000000007
def pascal():
matrix[0][0]=1;
for i in range(1001):
for j in range(1001):
if j==0 or j==i:
matrix[i][j]=1
else:
matrix[i][j] = (matrix[i-1][j-1]+matrix[i-1][j])%mod
a = int(input())
b = []
for i in range(a):
b.append(int(input()))
pascal()
r = 1
s = b[0]
for i in range(1,a):
r = (r*matrix[s + b[i]-1][b[i]-1])%mod
s += b[i]
print(r)
``` | instruction | 0 | 7,088 | 7 | 14,176 |
Yes | output | 1 | 7,088 | 7 | 14,177 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Kyoya Ootori has a bag with n colored balls that are colored with k different colors. The colors are labeled from 1 to k. Balls of the same color are indistinguishable. He draws balls from the bag one by one until the bag is empty. He noticed that he drew the last ball of color i before drawing the last ball of color i + 1 for all i from 1 to k - 1. Now he wonders how many different ways this can happen.
Input
The first line of input will have one integer k (1 β€ k β€ 1000) the number of colors.
Then, k lines will follow. The i-th line will contain ci, the number of balls of the i-th color (1 β€ ci β€ 1000).
The total number of balls doesn't exceed 1000.
Output
A single integer, the number of ways that Kyoya can draw the balls from the bag as described in the statement, modulo 1 000 000 007.
Examples
Input
3
2
2
1
Output
3
Input
4
1
2
3
4
Output
1680
Note
In the first sample, we have 2 balls of color 1, 2 balls of color 2, and 1 ball of color 3. The three ways for Kyoya are:
1 2 1 2 3
1 1 2 2 3
2 1 1 2 3
Submitted Solution:
```
mod = 10 ** 9 + 7
import math
def f(n): return math.factorial(n)
k = int(input())
c = [int(input()) for i in range(k)]
s, cnt = 0, 1
for i in c:
cnt *= f(s + i - 1) // f(i - 1) // f(s)
cnt %= mod
s += i
print(cnt)
``` | instruction | 0 | 7,089 | 7 | 14,178 |
Yes | output | 1 | 7,089 | 7 | 14,179 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Kyoya Ootori has a bag with n colored balls that are colored with k different colors. The colors are labeled from 1 to k. Balls of the same color are indistinguishable. He draws balls from the bag one by one until the bag is empty. He noticed that he drew the last ball of color i before drawing the last ball of color i + 1 for all i from 1 to k - 1. Now he wonders how many different ways this can happen.
Input
The first line of input will have one integer k (1 β€ k β€ 1000) the number of colors.
Then, k lines will follow. The i-th line will contain ci, the number of balls of the i-th color (1 β€ ci β€ 1000).
The total number of balls doesn't exceed 1000.
Output
A single integer, the number of ways that Kyoya can draw the balls from the bag as described in the statement, modulo 1 000 000 007.
Examples
Input
3
2
2
1
Output
3
Input
4
1
2
3
4
Output
1680
Note
In the first sample, we have 2 balls of color 1, 2 balls of color 2, and 1 ball of color 3. The three ways for Kyoya are:
1 2 1 2 3
1 1 2 2 3
2 1 1 2 3
Submitted Solution:
```
from math import factorial
n = int(input())
ans = 1
s = 0
mod = (10**9) + 7
for i in range(n):
a = int(input())
ans *= factorial(s+a-1)//(factorial(s) * factorial(a-1))
ans = ans%mod
s += a
print(ans)
``` | instruction | 0 | 7,090 | 7 | 14,180 |
Yes | output | 1 | 7,090 | 7 | 14,181 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Kyoya Ootori has a bag with n colored balls that are colored with k different colors. The colors are labeled from 1 to k. Balls of the same color are indistinguishable. He draws balls from the bag one by one until the bag is empty. He noticed that he drew the last ball of color i before drawing the last ball of color i + 1 for all i from 1 to k - 1. Now he wonders how many different ways this can happen.
Input
The first line of input will have one integer k (1 β€ k β€ 1000) the number of colors.
Then, k lines will follow. The i-th line will contain ci, the number of balls of the i-th color (1 β€ ci β€ 1000).
The total number of balls doesn't exceed 1000.
Output
A single integer, the number of ways that Kyoya can draw the balls from the bag as described in the statement, modulo 1 000 000 007.
Examples
Input
3
2
2
1
Output
3
Input
4
1
2
3
4
Output
1680
Note
In the first sample, we have 2 balls of color 1, 2 balls of color 2, and 1 ball of color 3. The three ways for Kyoya are:
1 2 1 2 3
1 1 2 2 3
2 1 1 2 3
Submitted Solution:
```
def fact(i):
if(i==0 or i==1):
return 1
else:
return(fact(i-1)*i)
n=int(input())
list1=[]
sum=0
product=1
for x in range(n):
list1.append(int(input()))
sum+=list1[x]
for x in range(n-2):
product*=fact(list1[x])
product=product*fact(list1[n-2]-1)*fact(list1[n-1]-1)
print((fact(sum-2)//product)%1000000007)
``` | instruction | 0 | 7,091 | 7 | 14,182 |
No | output | 1 | 7,091 | 7 | 14,183 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Kyoya Ootori has a bag with n colored balls that are colored with k different colors. The colors are labeled from 1 to k. Balls of the same color are indistinguishable. He draws balls from the bag one by one until the bag is empty. He noticed that he drew the last ball of color i before drawing the last ball of color i + 1 for all i from 1 to k - 1. Now he wonders how many different ways this can happen.
Input
The first line of input will have one integer k (1 β€ k β€ 1000) the number of colors.
Then, k lines will follow. The i-th line will contain ci, the number of balls of the i-th color (1 β€ ci β€ 1000).
The total number of balls doesn't exceed 1000.
Output
A single integer, the number of ways that Kyoya can draw the balls from the bag as described in the statement, modulo 1 000 000 007.
Examples
Input
3
2
2
1
Output
3
Input
4
1
2
3
4
Output
1680
Note
In the first sample, we have 2 balls of color 1, 2 balls of color 2, and 1 ball of color 3. The three ways for Kyoya are:
1 2 1 2 3
1 1 2 2 3
2 1 1 2 3
Submitted Solution:
```
import math
def nCr(n, r):
return (math.factorial(n) / (math.factorial(r)
* math.factorial(n - r)))
mod = 1000000007
n = int(input())
data = []
for i in range(n):
data.append(int(input()))
ans = 1
total = data[0]
for i in range(1,n):
total += data[i]
ans *= int(nCr(total-1,data[i]-1))
ans %= mod
print(int(ans))
``` | instruction | 0 | 7,092 | 7 | 14,184 |
No | output | 1 | 7,092 | 7 | 14,185 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Kyoya Ootori has a bag with n colored balls that are colored with k different colors. The colors are labeled from 1 to k. Balls of the same color are indistinguishable. He draws balls from the bag one by one until the bag is empty. He noticed that he drew the last ball of color i before drawing the last ball of color i + 1 for all i from 1 to k - 1. Now he wonders how many different ways this can happen.
Input
The first line of input will have one integer k (1 β€ k β€ 1000) the number of colors.
Then, k lines will follow. The i-th line will contain ci, the number of balls of the i-th color (1 β€ ci β€ 1000).
The total number of balls doesn't exceed 1000.
Output
A single integer, the number of ways that Kyoya can draw the balls from the bag as described in the statement, modulo 1 000 000 007.
Examples
Input
3
2
2
1
Output
3
Input
4
1
2
3
4
Output
1680
Note
In the first sample, we have 2 balls of color 1, 2 balls of color 2, and 1 ball of color 3. The three ways for Kyoya are:
1 2 1 2 3
1 1 2 2 3
2 1 1 2 3
Submitted Solution:
```
k=int(input())
l=[int(input()) for i in range(k)]
s=0
ans=[0]*k
ans[0]=1
MOD=10**9+7
fact=[0]*(10**6+5)
fact[0]=1
for i in range(1,10**6+5):
fact[i]=(fact[i-1]*i)%MOD
#print(fact[0:10])
def c(n,k):
if k>=n:
return 1
if k==0 or k==n:
return 1
return fact[n]//(fact[k]*fact[n-k])%MOD
ans=1
sm=l[0]
for i in range(1,k):
curr=l[i]
#ans[i]=ans[i-1]+
ans=ans*(c(sm+curr-1,curr-1))
ans%=MOD
sm+=l[i]
print(ans)
``` | instruction | 0 | 7,093 | 7 | 14,186 |
No | output | 1 | 7,093 | 7 | 14,187 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Kyoya Ootori has a bag with n colored balls that are colored with k different colors. The colors are labeled from 1 to k. Balls of the same color are indistinguishable. He draws balls from the bag one by one until the bag is empty. He noticed that he drew the last ball of color i before drawing the last ball of color i + 1 for all i from 1 to k - 1. Now he wonders how many different ways this can happen.
Input
The first line of input will have one integer k (1 β€ k β€ 1000) the number of colors.
Then, k lines will follow. The i-th line will contain ci, the number of balls of the i-th color (1 β€ ci β€ 1000).
The total number of balls doesn't exceed 1000.
Output
A single integer, the number of ways that Kyoya can draw the balls from the bag as described in the statement, modulo 1 000 000 007.
Examples
Input
3
2
2
1
Output
3
Input
4
1
2
3
4
Output
1680
Note
In the first sample, we have 2 balls of color 1, 2 balls of color 2, and 1 ball of color 3. The three ways for Kyoya are:
1 2 1 2 3
1 1 2 2 3
2 1 1 2 3
Submitted Solution:
```
from math import exp
def pfold (arr):
return arr[0] * pfold (arr[1:]) if arr else 1
def pscan (x, arr):
arr = (pscan (x * arr[-1], arr[:-1]) if arr else [])
arr.append(x)
return arr
def P(n, r):
return pfold(range(n, n-r, -1))
def F(n):
return P(n, n)
#return reduce(op.mul, range(n, 0, -1), 1)
def C(n, r):
if (r > n): return 0
r = min(r, n-r)
return P(n, r)//F(r)
def AC(a, b):
return C(a+b-1, b-1)
def CCC(n, k):
return AC(n, k)/F(k)
def Cat(n):
return C(2*n,n+1)/n
def Cat2(n):
return
def dot(a,b):
return sum(i*j for i, j in zip(a,b))
def Catray(n):
arr = [1]
for i in range(1,n):
arr = arr + [dot(arr,arr[::-1])]
return arr
# binomial distribution:
# with an event E which has probability p of occuring every try,
# what is the chance of E occuring exactly k times from n tries
def Bd (n, p, k):
return C(n,k)*p**k*(1-p)**(n-k)
# evaluate the sum of the binomial distribution in the range [0, k]
def BdS (n, p, k):
return sum(Bd(n, p, i) for i in range(k+1))
def Normal (mu, sigma, k):
return 0
# exponential distribution
def Ed (p, k):
return (1-p)*p**(k-1)
def EdS (p, k):
return 1 - p**k
def Pd (x, k):
return x**k/F(k) * exp(-x)
def PdS (x, k):
return (sum(pscan (1, [x/i for i in range (k, 0, -1)]))) * exp(-x)
#def PPP(n, k, m):
def nTermsSumToXInRangeAToB(n, x, a, b): # a <= b
x -= a*n
b -= a
if x < 0 or x > b*n:
return 0
else:
return nTermsUnderASumToX(n, x, b+1, 0)
def nTermsUnderASumToX(n, x, a, b):
if x < 0:
return 0
else:
return AC(x,n) - (n-b)*nTermsUnderASumToX(n, x-a, a, b+1)
def f(n, x, a, b):
return nTermsSumToXInRangeAToB(n, x, a, b)
M = 10**9+7
k = int(input())
v = 1
n = 0
for _ in range(k):
c = int(input())
v *= C(n+c-1,c-1)
c %= M
n+= c
print(v)
``` | instruction | 0 | 7,094 | 7 | 14,188 |
No | output | 1 | 7,094 | 7 | 14,189 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Anatoly lives in the university dorm as many other students do. As you know, cockroaches are also living there together with students. Cockroaches might be of two colors: black and red. There are n cockroaches living in Anatoly's room.
Anatoly just made all his cockroaches to form a single line. As he is a perfectionist, he would like the colors of cockroaches in the line to alternate. He has a can of black paint and a can of red paint. In one turn he can either swap any two cockroaches, or take any single cockroach and change it's color.
Help Anatoly find out the minimum number of turns he needs to make the colors of cockroaches in the line alternate.
Input
The first line of the input contains a single integer n (1 β€ n β€ 100 000) β the number of cockroaches.
The second line contains a string of length n, consisting of characters 'b' and 'r' that denote black cockroach and red cockroach respectively.
Output
Print one integer β the minimum number of moves Anatoly has to perform in order to make the colors of cockroaches in the line to alternate.
Examples
Input
5
rbbrr
Output
1
Input
5
bbbbb
Output
2
Input
3
rbr
Output
0
Note
In the first sample, Anatoly has to swap third and fourth cockroaches. He needs 1 turn to do this.
In the second sample, the optimum answer is to paint the second and the fourth cockroaches red. This requires 2 turns.
In the third sample, the colors of cockroaches in the line are alternating already, thus the answer is 0. | instruction | 0 | 7,157 | 7 | 14,314 |
Tags: greedy
Correct Solution:
```
n=int(input())
s=input()
e="rb"*(n//2)+"r"*(n%2)
w="br"*(n//2)+"b"*(n%2)
lenn=len(s)
f,r,b,rr,bb=0,0,0,0,0
for i in range(lenn):
if s[i]!=e[i]:
if s[i]=='r':
r+=1
else:
b+=1
if s[i]!=w[i]:
if s[i]=='r':
rr+=1
else:
bb+=1
f=min(max(r,b),max(rr,bb))
print(f)
``` | output | 1 | 7,157 | 7 | 14,315 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Anatoly lives in the university dorm as many other students do. As you know, cockroaches are also living there together with students. Cockroaches might be of two colors: black and red. There are n cockroaches living in Anatoly's room.
Anatoly just made all his cockroaches to form a single line. As he is a perfectionist, he would like the colors of cockroaches in the line to alternate. He has a can of black paint and a can of red paint. In one turn he can either swap any two cockroaches, or take any single cockroach and change it's color.
Help Anatoly find out the minimum number of turns he needs to make the colors of cockroaches in the line alternate.
Input
The first line of the input contains a single integer n (1 β€ n β€ 100 000) β the number of cockroaches.
The second line contains a string of length n, consisting of characters 'b' and 'r' that denote black cockroach and red cockroach respectively.
Output
Print one integer β the minimum number of moves Anatoly has to perform in order to make the colors of cockroaches in the line to alternate.
Examples
Input
5
rbbrr
Output
1
Input
5
bbbbb
Output
2
Input
3
rbr
Output
0
Note
In the first sample, Anatoly has to swap third and fourth cockroaches. He needs 1 turn to do this.
In the second sample, the optimum answer is to paint the second and the fourth cockroaches red. This requires 2 turns.
In the third sample, the colors of cockroaches in the line are alternating already, thus the answer is 0. | instruction | 0 | 7,158 | 7 | 14,316 |
Tags: greedy
Correct Solution:
```
n, cr = int(input()), [i for i in input()]
case_1 = (["r", "b"]*n)[0:n]
case_2 = (["b", "r"]*n)[0:n]
btor, rtob = 0, 0
ans = []
for i in range(len(cr)):
if (cr[i] != case_1[i]) :
if cr[i] == "r" :
rtob += 1
else :
btor += 1
ans.append(min([rtob, btor]) + abs(rtob - btor))
btor, rtob = 0, 0
for i in range(len(cr)):
if (cr[i] != case_2[i]) :
if cr[i] == "r" :
rtob += 1
else :
btor += 1
ans.append(min([rtob, btor]) + abs(rtob - btor))
print(min(ans))
``` | output | 1 | 7,158 | 7 | 14,317 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Anatoly lives in the university dorm as many other students do. As you know, cockroaches are also living there together with students. Cockroaches might be of two colors: black and red. There are n cockroaches living in Anatoly's room.
Anatoly just made all his cockroaches to form a single line. As he is a perfectionist, he would like the colors of cockroaches in the line to alternate. He has a can of black paint and a can of red paint. In one turn he can either swap any two cockroaches, or take any single cockroach and change it's color.
Help Anatoly find out the minimum number of turns he needs to make the colors of cockroaches in the line alternate.
Input
The first line of the input contains a single integer n (1 β€ n β€ 100 000) β the number of cockroaches.
The second line contains a string of length n, consisting of characters 'b' and 'r' that denote black cockroach and red cockroach respectively.
Output
Print one integer β the minimum number of moves Anatoly has to perform in order to make the colors of cockroaches in the line to alternate.
Examples
Input
5
rbbrr
Output
1
Input
5
bbbbb
Output
2
Input
3
rbr
Output
0
Note
In the first sample, Anatoly has to swap third and fourth cockroaches. He needs 1 turn to do this.
In the second sample, the optimum answer is to paint the second and the fourth cockroaches red. This requires 2 turns.
In the third sample, the colors of cockroaches in the line are alternating already, thus the answer is 0. | instruction | 0 | 7,159 | 7 | 14,318 |
Tags: greedy
Correct Solution:
```
def cal( s , c ):
w = [0 , 0]
for i in range(len(s)):
if s[i] != c: w[ i % 2 ] += 1
c = 'r' if c == 'b' else 'b'
return max(w[0], w[1])
n = int( input() )
s = input()
print( min( cal( s , 'r' ) , cal( s , 'b' ) ) )
``` | output | 1 | 7,159 | 7 | 14,319 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Anatoly lives in the university dorm as many other students do. As you know, cockroaches are also living there together with students. Cockroaches might be of two colors: black and red. There are n cockroaches living in Anatoly's room.
Anatoly just made all his cockroaches to form a single line. As he is a perfectionist, he would like the colors of cockroaches in the line to alternate. He has a can of black paint and a can of red paint. In one turn he can either swap any two cockroaches, or take any single cockroach and change it's color.
Help Anatoly find out the minimum number of turns he needs to make the colors of cockroaches in the line alternate.
Input
The first line of the input contains a single integer n (1 β€ n β€ 100 000) β the number of cockroaches.
The second line contains a string of length n, consisting of characters 'b' and 'r' that denote black cockroach and red cockroach respectively.
Output
Print one integer β the minimum number of moves Anatoly has to perform in order to make the colors of cockroaches in the line to alternate.
Examples
Input
5
rbbrr
Output
1
Input
5
bbbbb
Output
2
Input
3
rbr
Output
0
Note
In the first sample, Anatoly has to swap third and fourth cockroaches. He needs 1 turn to do this.
In the second sample, the optimum answer is to paint the second and the fourth cockroaches red. This requires 2 turns.
In the third sample, the colors of cockroaches in the line are alternating already, thus the answer is 0. | instruction | 0 | 7,160 | 7 | 14,320 |
Tags: greedy
Correct Solution:
```
n = int(input())
cockroaches = input()
def get_color_range(start_color):
color = start_color
while True:
if color == 'b':
color = 'r'
else:
color ='b'
yield color
color_range1 = get_color_range('r')
color_range2 = get_color_range('b')
r1 = r2 = b1 = b2 = 0
for color in cockroaches:
if color != next(color_range1):
if color == 'r':
r1 += 1
else:
b1 += 1
if color != next(color_range2):
if color == 'r':
r2 += 1
else:
b2 += 1
variant1 = min(r1, b1) + abs(r1 - b1)
variant2 = min(r2, b2) + abs(r2 - b2)
print(min(variant1, variant2))
``` | output | 1 | 7,160 | 7 | 14,321 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Anatoly lives in the university dorm as many other students do. As you know, cockroaches are also living there together with students. Cockroaches might be of two colors: black and red. There are n cockroaches living in Anatoly's room.
Anatoly just made all his cockroaches to form a single line. As he is a perfectionist, he would like the colors of cockroaches in the line to alternate. He has a can of black paint and a can of red paint. In one turn he can either swap any two cockroaches, or take any single cockroach and change it's color.
Help Anatoly find out the minimum number of turns he needs to make the colors of cockroaches in the line alternate.
Input
The first line of the input contains a single integer n (1 β€ n β€ 100 000) β the number of cockroaches.
The second line contains a string of length n, consisting of characters 'b' and 'r' that denote black cockroach and red cockroach respectively.
Output
Print one integer β the minimum number of moves Anatoly has to perform in order to make the colors of cockroaches in the line to alternate.
Examples
Input
5
rbbrr
Output
1
Input
5
bbbbb
Output
2
Input
3
rbr
Output
0
Note
In the first sample, Anatoly has to swap third and fourth cockroaches. He needs 1 turn to do this.
In the second sample, the optimum answer is to paint the second and the fourth cockroaches red. This requires 2 turns.
In the third sample, the colors of cockroaches in the line are alternating already, thus the answer is 0. | instruction | 0 | 7,161 | 7 | 14,322 |
Tags: greedy
Correct Solution:
```
# -*- coding: utf-8 -*-
"""
Created on Sat Sep 17 19:15:41 2016
@author: bigu
"""
n = int(input())
line = input()
black0 = black1 = red0 = red1 = 0
for i,cock in enumerate(line):
if i%2==0 and cock == 'r':
red0+=1
elif i%2==1 and cock == 'r':
red1+=1
elif i%2==0 and cock == 'b':
black0+=1
elif i%2==1 and cock == 'b':
black1+=1
ans = min(max(red0,black1),max(red1,black0))
print(ans)
``` | output | 1 | 7,161 | 7 | 14,323 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Anatoly lives in the university dorm as many other students do. As you know, cockroaches are also living there together with students. Cockroaches might be of two colors: black and red. There are n cockroaches living in Anatoly's room.
Anatoly just made all his cockroaches to form a single line. As he is a perfectionist, he would like the colors of cockroaches in the line to alternate. He has a can of black paint and a can of red paint. In one turn he can either swap any two cockroaches, or take any single cockroach and change it's color.
Help Anatoly find out the minimum number of turns he needs to make the colors of cockroaches in the line alternate.
Input
The first line of the input contains a single integer n (1 β€ n β€ 100 000) β the number of cockroaches.
The second line contains a string of length n, consisting of characters 'b' and 'r' that denote black cockroach and red cockroach respectively.
Output
Print one integer β the minimum number of moves Anatoly has to perform in order to make the colors of cockroaches in the line to alternate.
Examples
Input
5
rbbrr
Output
1
Input
5
bbbbb
Output
2
Input
3
rbr
Output
0
Note
In the first sample, Anatoly has to swap third and fourth cockroaches. He needs 1 turn to do this.
In the second sample, the optimum answer is to paint the second and the fourth cockroaches red. This requires 2 turns.
In the third sample, the colors of cockroaches in the line are alternating already, thus the answer is 0. | instruction | 0 | 7,162 | 7 | 14,324 |
Tags: greedy
Correct Solution:
```
def f(p):
cnt1 = sum(a[i] != p[i] == 1 for i in range(n))
cnt2 = sum(a[i] != p[i] == 0 for i in range(n))
res = max(cnt1, cnt2)
return res
n = int(input())
a = [int(i == 'r') for i in input()]
p1 = [i % 2 for i in range(n)]
p2 = [(i + 1) % 2 for i in range(n)]
ans = min(f(p1), f(p2))
print(ans)
``` | output | 1 | 7,162 | 7 | 14,325 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Anatoly lives in the university dorm as many other students do. As you know, cockroaches are also living there together with students. Cockroaches might be of two colors: black and red. There are n cockroaches living in Anatoly's room.
Anatoly just made all his cockroaches to form a single line. As he is a perfectionist, he would like the colors of cockroaches in the line to alternate. He has a can of black paint and a can of red paint. In one turn he can either swap any two cockroaches, or take any single cockroach and change it's color.
Help Anatoly find out the minimum number of turns he needs to make the colors of cockroaches in the line alternate.
Input
The first line of the input contains a single integer n (1 β€ n β€ 100 000) β the number of cockroaches.
The second line contains a string of length n, consisting of characters 'b' and 'r' that denote black cockroach and red cockroach respectively.
Output
Print one integer β the minimum number of moves Anatoly has to perform in order to make the colors of cockroaches in the line to alternate.
Examples
Input
5
rbbrr
Output
1
Input
5
bbbbb
Output
2
Input
3
rbr
Output
0
Note
In the first sample, Anatoly has to swap third and fourth cockroaches. He needs 1 turn to do this.
In the second sample, the optimum answer is to paint the second and the fourth cockroaches red. This requires 2 turns.
In the third sample, the colors of cockroaches in the line are alternating already, thus the answer is 0. | instruction | 0 | 7,163 | 7 | 14,326 |
Tags: greedy
Correct Solution:
```
n=input()
word=input()
c=0
sum1,sum2,sum3,sum4=0,0,0,0
for i in word:
if c==0 :
if i=='r':
sum1+=1
else :
sum2+=1
c=1
else :
if i=='b':
sum3+=1
else :
sum4+=1
c=0
print(min(max(sum1,sum3),max(sum2,sum4)))
``` | output | 1 | 7,163 | 7 | 14,327 |
Provide tags and a correct Python 3 solution for this coding contest problem.
Anatoly lives in the university dorm as many other students do. As you know, cockroaches are also living there together with students. Cockroaches might be of two colors: black and red. There are n cockroaches living in Anatoly's room.
Anatoly just made all his cockroaches to form a single line. As he is a perfectionist, he would like the colors of cockroaches in the line to alternate. He has a can of black paint and a can of red paint. In one turn he can either swap any two cockroaches, or take any single cockroach and change it's color.
Help Anatoly find out the minimum number of turns he needs to make the colors of cockroaches in the line alternate.
Input
The first line of the input contains a single integer n (1 β€ n β€ 100 000) β the number of cockroaches.
The second line contains a string of length n, consisting of characters 'b' and 'r' that denote black cockroach and red cockroach respectively.
Output
Print one integer β the minimum number of moves Anatoly has to perform in order to make the colors of cockroaches in the line to alternate.
Examples
Input
5
rbbrr
Output
1
Input
5
bbbbb
Output
2
Input
3
rbr
Output
0
Note
In the first sample, Anatoly has to swap third and fourth cockroaches. He needs 1 turn to do this.
In the second sample, the optimum answer is to paint the second and the fourth cockroaches red. This requires 2 turns.
In the third sample, the colors of cockroaches in the line are alternating already, thus the answer is 0. | instruction | 0 | 7,164 | 7 | 14,328 |
Tags: greedy
Correct Solution:
```
def dist(s, choice):
r_diff = 0
b_diff = 0
for i in range(len(s)):
if choice[i] != s[i]:
if s[i] == 'r':
r_diff += 1
else:
b_diff += 1
min_diff = min(r_diff, b_diff)
return min_diff + (r_diff - min_diff) + (b_diff - min_diff)
if __name__ == '__main__':
n = int(input())
a = list(input())
choice_one = []
choice_two = []
for i in range(len(a)):
if i % 2 == 0:
choice_one.append('r')
choice_two.append('b')
else:
choice_one.append('b')
choice_two.append('r')
print(min(dist(a, choice_one), dist(a, choice_two)))
``` | output | 1 | 7,164 | 7 | 14,329 |
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
Anatoly lives in the university dorm as many other students do. As you know, cockroaches are also living there together with students. Cockroaches might be of two colors: black and red. There are n cockroaches living in Anatoly's room.
Anatoly just made all his cockroaches to form a single line. As he is a perfectionist, he would like the colors of cockroaches in the line to alternate. He has a can of black paint and a can of red paint. In one turn he can either swap any two cockroaches, or take any single cockroach and change it's color.
Help Anatoly find out the minimum number of turns he needs to make the colors of cockroaches in the line alternate.
Input
The first line of the input contains a single integer n (1 β€ n β€ 100 000) β the number of cockroaches.
The second line contains a string of length n, consisting of characters 'b' and 'r' that denote black cockroach and red cockroach respectively.
Output
Print one integer β the minimum number of moves Anatoly has to perform in order to make the colors of cockroaches in the line to alternate.
Examples
Input
5
rbbrr
Output
1
Input
5
bbbbb
Output
2
Input
3
rbr
Output
0
Note
In the first sample, Anatoly has to swap third and fourth cockroaches. He needs 1 turn to do this.
In the second sample, the optimum answer is to paint the second and the fourth cockroaches red. This requires 2 turns.
In the third sample, the colors of cockroaches in the line are alternating already, thus the answer is 0.
Submitted Solution:
```
n=int(input())
m=input()
rb={'r':0,'b':0}
br={'r':0,'b':0}
for i in range(n):
if i%2:
if m[i]=='b':
br['b']+=1
else:
rb['r']+=1
else:
if m[i]=='r':
br['r']+=1
else:
rb['b']+=1
rbs=min(rb['b'],rb['r'])+abs(rb['b']-rb['r'])
brs=min(br['b'],br['r'])+abs(br['b']-br['r'])
print(min(rbs,brs))
``` | instruction | 0 | 7,165 | 7 | 14,330 |
Yes | output | 1 | 7,165 | 7 | 14,331 |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.