id int64 1 3.71k | title stringlengths 3 79 | difficulty stringclasses 3
values | description stringlengths 430 25.4k | tags stringlengths 0 131 | language stringclasses 19
values | solution stringlengths 47 20.6k |
|---|---|---|---|---|---|---|
1 | Two Sum | Easy | <p>Given an array of integers <code>nums</code> and an integer <code>target</code>, return <em>indices of the two numbers such that they add up to <code>target</code></em>.</p>
<p>You may assume that each input would have <strong><em>exactly</em> one solution</strong>, and you may not use the <em>same</em> elemen... | Array; Hash Table | C | #include <stdlib.h>
int* twoSum(int* nums, int numsSize, int target, int* returnSize) {
int capacity = 1;
while (capacity < numsSize * 2) capacity <<= 1;
int* keys = malloc(capacity * sizeof(int));
int* vals = malloc(capacity * sizeof(int));
char* used = calloc(capacity, sizeof(char));
if (!key... |
1 | Two Sum | Easy | <p>Given an array of integers <code>nums</code> and an integer <code>target</code>, return <em>indices of the two numbers such that they add up to <code>target</code></em>.</p>
<p>You may assume that each input would have <strong><em>exactly</em> one solution</strong>, and you may not use the <em>same</em> elemen... | Array; Hash Table | Cangjie | class Solution {
func twoSum(nums: Array<Int64>, target: Int64): Array<Int64> {
let d = HashMap<Int64, Int64>()
for (i in 0..nums.size) {
if (d.contains(target - nums[i])) {
return [d[target - nums[i]], i]
}
d[nums[i]] = i
}
... |
1 | Two Sum | Easy | <p>Given an array of integers <code>nums</code> and an integer <code>target</code>, return <em>indices of the two numbers such that they add up to <code>target</code></em>.</p>
<p>You may assume that each input would have <strong><em>exactly</em> one solution</strong>, and you may not use the <em>same</em> elemen... | Array; Hash Table | C++ | class Solution {
public:
vector<int> twoSum(vector<int>& nums, int target) {
unordered_map<int, int> d;
for (int i = 0;; ++i) {
int x = nums[i];
int y = target - x;
if (d.contains(y)) {
return {d[y], i};
}
d[x] = i;
... |
1 | Two Sum | Easy | <p>Given an array of integers <code>nums</code> and an integer <code>target</code>, return <em>indices of the two numbers such that they add up to <code>target</code></em>.</p>
<p>You may assume that each input would have <strong><em>exactly</em> one solution</strong>, and you may not use the <em>same</em> elemen... | Array; Hash Table | C# | public class Solution {
public int[] TwoSum(int[] nums, int target) {
var d = new Dictionary<int, int>();
for (int i = 0, j; ; ++i) {
int x = nums[i];
int y = target - x;
if (d.TryGetValue(y, out j)) {
return new [] {j, i};
}
... |
1 | Two Sum | Easy | <p>Given an array of integers <code>nums</code> and an integer <code>target</code>, return <em>indices of the two numbers such that they add up to <code>target</code></em>.</p>
<p>You may assume that each input would have <strong><em>exactly</em> one solution</strong>, and you may not use the <em>same</em> elemen... | Array; Hash Table | Go | func twoSum(nums []int, target int) []int {
d := map[int]int{}
for i := 0; ; i++ {
x := nums[i]
y := target - x
if j, ok := d[y]; ok {
return []int{j, i}
}
d[x] = i
}
}
|
1 | Two Sum | Easy | <p>Given an array of integers <code>nums</code> and an integer <code>target</code>, return <em>indices of the two numbers such that they add up to <code>target</code></em>.</p>
<p>You may assume that each input would have <strong><em>exactly</em> one solution</strong>, and you may not use the <em>same</em> elemen... | Array; Hash Table | Java | class Solution {
public int[] twoSum(int[] nums, int target) {
Map<Integer, Integer> d = new HashMap<>();
for (int i = 0;; ++i) {
int x = nums[i];
int y = target - x;
if (d.containsKey(y)) {
return new int[] {d.get(y), i};
}
... |
1 | Two Sum | Easy | <p>Given an array of integers <code>nums</code> and an integer <code>target</code>, return <em>indices of the two numbers such that they add up to <code>target</code></em>.</p>
<p>You may assume that each input would have <strong><em>exactly</em> one solution</strong>, and you may not use the <em>same</em> elemen... | Array; Hash Table | JavaScript | /**
* @param {number[]} nums
* @param {number} target
* @return {number[]}
*/
var twoSum = function (nums, target) {
const d = new Map();
for (let i = 0; ; ++i) {
const x = nums[i];
const y = target - x;
if (d.has(y)) {
return [d.get(y), i];
}
d.set(x, i);... |
1 | Two Sum | Easy | <p>Given an array of integers <code>nums</code> and an integer <code>target</code>, return <em>indices of the two numbers such that they add up to <code>target</code></em>.</p>
<p>You may assume that each input would have <strong><em>exactly</em> one solution</strong>, and you may not use the <em>same</em> elemen... | Array; Hash Table | Kotlin | class Solution {
fun twoSum(nums: IntArray, target: Int): IntArray {
val m = mutableMapOf<Int, Int>()
nums.forEachIndexed { i, x ->
val y = target - x
val j = m.get(y)
if (j != null) {
return intArrayOf(j, i)
}
m[x] = i
... |
1 | Two Sum | Easy | <p>Given an array of integers <code>nums</code> and an integer <code>target</code>, return <em>indices of the two numbers such that they add up to <code>target</code></em>.</p>
<p>You may assume that each input would have <strong><em>exactly</em> one solution</strong>, and you may not use the <em>same</em> elemen... | Array; Hash Table | Nim | import std/enumerate
import std/tables
proc twoSum(nums: seq[int], target: int): seq[int] =
var d = initTable[int, int]()
for i, x in nums.pairs():
let y = target - x
if d.hasKey(y):
return @[d[y], i]
d[x] = i
return @[]
|
1 | Two Sum | Easy | <p>Given an array of integers <code>nums</code> and an integer <code>target</code>, return <em>indices of the two numbers such that they add up to <code>target</code></em>.</p>
<p>You may assume that each input would have <strong><em>exactly</em> one solution</strong>, and you may not use the <em>same</em> elemen... | Array; Hash Table | PHP | class Solution {
/**
* @param Integer[] $nums
* @param Integer $target
* @return Integer[]
*/
function twoSum($nums, $target) {
$d = [];
foreach ($nums as $i => $x) {
$y = $target - $x;
if (isset($d[$y])) {
return [$d[$y], $i];
... |
1 | Two Sum | Easy | <p>Given an array of integers <code>nums</code> and an integer <code>target</code>, return <em>indices of the two numbers such that they add up to <code>target</code></em>.</p>
<p>You may assume that each input would have <strong><em>exactly</em> one solution</strong>, and you may not use the <em>same</em> elemen... | Array; Hash Table | Python | class Solution:
def twoSum(self, nums: List[int], target: int) -> List[int]:
d = {}
for i, x in enumerate(nums):
if (y := target - x) in d:
return [d[y], i]
d[x] = i
|
1 | Two Sum | Easy | <p>Given an array of integers <code>nums</code> and an integer <code>target</code>, return <em>indices of the two numbers such that they add up to <code>target</code></em>.</p>
<p>You may assume that each input would have <strong><em>exactly</em> one solution</strong>, and you may not use the <em>same</em> elemen... | Array; Hash Table | Ruby | # @param {Integer[]} nums
# @param {Integer} target
# @return {Integer[]}
def two_sum(nums, target)
d = {}
nums.each_with_index do |x, i|
y = target - x
if d.key?(y)
return [d[y], i]
end
d[x] = i
end
end
|
1 | Two Sum | Easy | <p>Given an array of integers <code>nums</code> and an integer <code>target</code>, return <em>indices of the two numbers such that they add up to <code>target</code></em>.</p>
<p>You may assume that each input would have <strong><em>exactly</em> one solution</strong>, and you may not use the <em>same</em> elemen... | Array; Hash Table | Rust | use std::collections::HashMap;
impl Solution {
pub fn two_sum(nums: Vec<i32>, target: i32) -> Vec<i32> {
let mut d = HashMap::new();
for (i, &x) in nums.iter().enumerate() {
let y = target - x;
if let Some(&j) = d.get(&y) {
return vec![j as i32, i as i32];
... |
1 | Two Sum | Easy | <p>Given an array of integers <code>nums</code> and an integer <code>target</code>, return <em>indices of the two numbers such that they add up to <code>target</code></em>.</p>
<p>You may assume that each input would have <strong><em>exactly</em> one solution</strong>, and you may not use the <em>same</em> elemen... | Array; Hash Table | Scala | import scala.collection.mutable
object Solution {
def twoSum(nums: Array[Int], target: Int): Array[Int] = {
val d = mutable.Map[Int, Int]()
var ans: Array[Int] = Array()
for (i <- nums.indices if ans.isEmpty) {
val x = nums(i)
val y = target - x
if (d.con... |
1 | Two Sum | Easy | <p>Given an array of integers <code>nums</code> and an integer <code>target</code>, return <em>indices of the two numbers such that they add up to <code>target</code></em>.</p>
<p>You may assume that each input would have <strong><em>exactly</em> one solution</strong>, and you may not use the <em>same</em> elemen... | Array; Hash Table | Swift | class Solution {
func twoSum(_ nums: [Int], _ target: Int) -> [Int] {
var d = [Int: Int]()
for (i, x) in nums.enumerated() {
let y = target - x
if let j = d[y] {
return [j, i]
}
d[x] = i
}
return []
}
}
|
1 | Two Sum | Easy | <p>Given an array of integers <code>nums</code> and an integer <code>target</code>, return <em>indices of the two numbers such that they add up to <code>target</code></em>.</p>
<p>You may assume that each input would have <strong><em>exactly</em> one solution</strong>, and you may not use the <em>same</em> elemen... | Array; Hash Table | TypeScript | function twoSum(nums: number[], target: number): number[] {
const d = new Map<number, number>();
for (let i = 0; ; ++i) {
const x = nums[i];
const y = target - x;
if (d.has(y)) {
return [d.get(y)!, i];
}
d.set(x, i);
}
}
|
2 | Add Two Numbers | Medium | <p>You are given two <strong>non-empty</strong> linked lists representing two non-negative integers. The digits are stored in <strong>reverse order</strong>, and each of their nodes contains a single digit. Add the two numbers and return the sum as a linked list.</p>
<p>You may assume the two numbers do not conta... | Recursion; Linked List; Math | C |
/**
* Definition for singly-linked list.
* struct ListNode {
* int val;
* struct ListNode *next;
* };
*/
struct ListNode* addTwoNumbers(struct ListNode* l1, struct ListNode* l2) {
struct ListNode* dummy = (struct ListNode*) malloc(sizeof(struct ListNode));
dummy->val = 0;
dummy->next = NULL;... |
2 | Add Two Numbers | Medium | <p>You are given two <strong>non-empty</strong> linked lists representing two non-negative integers. The digits are stored in <strong>reverse order</strong>, and each of their nodes contains a single digit. Add the two numbers and return the sum as a linked list.</p>
<p>You may assume the two numbers do not conta... | Recursion; Linked List; Math | C++ | /**
* Definition for singly-linked list.
* struct ListNode {
* int val;
* ListNode *next;
* ListNode() : val(0), next(nullptr) {}
* ListNode(int x) : val(x), next(nullptr) {}
* ListNode(int x, ListNode *next) : val(x), next(next) {}
* };
*/
class Solution {
public:
ListNode* addTwoNumbe... |
2 | Add Two Numbers | Medium | <p>You are given two <strong>non-empty</strong> linked lists representing two non-negative integers. The digits are stored in <strong>reverse order</strong>, and each of their nodes contains a single digit. Add the two numbers and return the sum as a linked list.</p>
<p>You may assume the two numbers do not conta... | Recursion; Linked List; Math | C# | /**
* Definition for singly-linked list.
* public class ListNode {
* public int val;
* public ListNode next;
* public ListNode(int val=0, ListNode next=null) {
* this.val = val;
* this.next = next;
* }
* }
*/
public class Solution {
public ListNode AddTwoNumbers(ListNode l1... |
2 | Add Two Numbers | Medium | <p>You are given two <strong>non-empty</strong> linked lists representing two non-negative integers. The digits are stored in <strong>reverse order</strong>, and each of their nodes contains a single digit. Add the two numbers and return the sum as a linked list.</p>
<p>You may assume the two numbers do not conta... | Recursion; Linked List; Math | Go | /**
* Definition for singly-linked list.
* type ListNode struct {
* Val int
* Next *ListNode
* }
*/
func addTwoNumbers(l1 *ListNode, l2 *ListNode) *ListNode {
dummy := &ListNode{}
carry := 0
cur := dummy
for l1 != nil || l2 != nil || carry != 0 {
s := carry
if l1 != nil {
s += l1.Val
}
if l... |
2 | Add Two Numbers | Medium | <p>You are given two <strong>non-empty</strong> linked lists representing two non-negative integers. The digits are stored in <strong>reverse order</strong>, and each of their nodes contains a single digit. Add the two numbers and return the sum as a linked list.</p>
<p>You may assume the two numbers do not conta... | Recursion; Linked List; Math | Java | /**
* Definition for singly-linked list.
* public class ListNode {
* int val;
* ListNode next;
* ListNode() {}
* ListNode(int val) { this.val = val; }
* ListNode(int val, ListNode next) { this.val = val; this.next = next; }
* }
*/
class Solution {
public ListNode addTwoNumbers(ListNode ... |
2 | Add Two Numbers | Medium | <p>You are given two <strong>non-empty</strong> linked lists representing two non-negative integers. The digits are stored in <strong>reverse order</strong>, and each of their nodes contains a single digit. Add the two numbers and return the sum as a linked list.</p>
<p>You may assume the two numbers do not conta... | Recursion; Linked List; Math | JavaScript | /**
* Definition for singly-linked list.
* function ListNode(val, next) {
* this.val = (val===undefined ? 0 : val)
* this.next = (next===undefined ? null : next)
* }
*/
/**
* @param {ListNode} l1
* @param {ListNode} l2
* @return {ListNode}
*/
var addTwoNumbers = function (l1, l2) {
const dummy = n... |
2 | Add Two Numbers | Medium | <p>You are given two <strong>non-empty</strong> linked lists representing two non-negative integers. The digits are stored in <strong>reverse order</strong>, and each of their nodes contains a single digit. Add the two numbers and return the sum as a linked list.</p>
<p>You may assume the two numbers do not conta... | Recursion; Linked List; Math | Nim | #[
# Driver code in the solution file
# Definition for singly-linked list.
type
Node[int] = ref object
value: int
next: Node[int]
SinglyLinkedList[T] = object
head, tail: Node[T]
]#
# More efficient code churning ...
proc addTwoNumbers(l1: var SinglyLinkedList, l2: var Sing... |
2 | Add Two Numbers | Medium | <p>You are given two <strong>non-empty</strong> linked lists representing two non-negative integers. The digits are stored in <strong>reverse order</strong>, and each of their nodes contains a single digit. Add the two numbers and return the sum as a linked list.</p>
<p>You may assume the two numbers do not conta... | Recursion; Linked List; Math | PHP | /**
* Definition for a singly-linked list.
* class ListNode {
* public $val = 0;
* public $next = null;
* function __construct($val = 0, $next = null) {
* $this->val = $val;
* $this->next = $next;
* }
* }
*/
class Solution {
/**
* @param ListNode $l1
* @param List... |
2 | Add Two Numbers | Medium | <p>You are given two <strong>non-empty</strong> linked lists representing two non-negative integers. The digits are stored in <strong>reverse order</strong>, and each of their nodes contains a single digit. Add the two numbers and return the sum as a linked list.</p>
<p>You may assume the two numbers do not conta... | Recursion; Linked List; Math | Python | # Definition for singly-linked list.
# class ListNode:
# def __init__(self, val=0, next=None):
# self.val = val
# self.next = next
class Solution:
def addTwoNumbers(
self, l1: Optional[ListNode], l2: Optional[ListNode]
) -> Optional[ListNode]:
dummy = ListNode()
carry... |
2 | Add Two Numbers | Medium | <p>You are given two <strong>non-empty</strong> linked lists representing two non-negative integers. The digits are stored in <strong>reverse order</strong>, and each of their nodes contains a single digit. Add the two numbers and return the sum as a linked list.</p>
<p>You may assume the two numbers do not conta... | Recursion; Linked List; Math | Ruby | # Definition for singly-linked list.
# class ListNode
# attr_accessor :val, :next
# def initialize(val = 0, _next = nil)
# @val = val
# @next = _next
# end
# end
# @param {ListNode} l1
# @param {ListNode} l2
# @return {ListNode}
def add_two_numbers(l1, l2)
dummy = ListNode.new()
carr... |
2 | Add Two Numbers | Medium | <p>You are given two <strong>non-empty</strong> linked lists representing two non-negative integers. The digits are stored in <strong>reverse order</strong>, and each of their nodes contains a single digit. Add the two numbers and return the sum as a linked list.</p>
<p>You may assume the two numbers do not conta... | Recursion; Linked List; Math | Rust | // Definition for singly-linked list.
// #[derive(PartialEq, Eq, Clone, Debug)]
// pub struct ListNode {
// pub val: i32,
// pub next: Option<Box<ListNode>>
// }
//
// impl ListNode {
// #[inline]
// fn new(val: i32) -> Self {
// ListNode {
// next: None,
// val
// }
// }
// }
impl Solutio... |
2 | Add Two Numbers | Medium | <p>You are given two <strong>non-empty</strong> linked lists representing two non-negative integers. The digits are stored in <strong>reverse order</strong>, and each of their nodes contains a single digit. Add the two numbers and return the sum as a linked list.</p>
<p>You may assume the two numbers do not conta... | Recursion; Linked List; Math | Swift | /**
* Definition for singly-linked list.
* public class ListNode {
* public var val: Int
* public var next: ListNode?
* public init() { self.val = 0; self.next = nil; }
* public init(_ val: Int) { self.val = val; self.next = nil; }
* public init(_ val: Int, _ next: ListNode?) { self.val = val... |
2 | Add Two Numbers | Medium | <p>You are given two <strong>non-empty</strong> linked lists representing two non-negative integers. The digits are stored in <strong>reverse order</strong>, and each of their nodes contains a single digit. Add the two numbers and return the sum as a linked list.</p>
<p>You may assume the two numbers do not conta... | Recursion; Linked List; Math | TypeScript | /**
* Definition for singly-linked list.
* class ListNode {
* val: number
* next: ListNode | null
* constructor(val?: number, next?: ListNode | null) {
* this.val = (val===undefined ? 0 : val)
* this.next = (next===undefined ? null : next)
* }
* }
*/
function addTwoNumbers(l1:... |
3 | Longest Substring Without Repeating Characters | Medium | <p>Given a string <code>s</code>, find the length of the <strong>longest</strong> <span data-keyword="substring-nonempty"><strong>substring</strong></span> without duplicate characters.</p>
<p> </p>
<p><strong class="example">Example 1:</strong></p>
<pre>
<strong>Input:</strong> s = "abcabcbb"
<strong>... | Hash Table; String; Sliding Window | C | int lengthOfLongestSubstring(char* s) {
int freq[256] = {0};
int l = 0, r = 0;
int ans = 0;
int len = strlen(s);
for (r = 0; r < len; r++) {
char c = s[r];
freq[(unsigned char) c]++;
while (freq[(unsigned char) c] > 1) {
freq[(unsigned char) s[l]]--;
... |
3 | Longest Substring Without Repeating Characters | Medium | <p>Given a string <code>s</code>, find the length of the <strong>longest</strong> <span data-keyword="substring-nonempty"><strong>substring</strong></span> without duplicate characters.</p>
<p> </p>
<p><strong class="example">Example 1:</strong></p>
<pre>
<strong>Input:</strong> s = "abcabcbb"
<strong>... | Hash Table; String; Sliding Window | C++ | class Solution {
public:
int lengthOfLongestSubstring(string s) {
int cnt[128]{};
int ans = 0, n = s.size();
for (int l = 0, r = 0; r < n; ++r) {
++cnt[s[r]];
while (cnt[s[r]] > 1) {
--cnt[s[l++]];
}
ans = max(ans, r - l + 1);
... |
3 | Longest Substring Without Repeating Characters | Medium | <p>Given a string <code>s</code>, find the length of the <strong>longest</strong> <span data-keyword="substring-nonempty"><strong>substring</strong></span> without duplicate characters.</p>
<p> </p>
<p><strong class="example">Example 1:</strong></p>
<pre>
<strong>Input:</strong> s = "abcabcbb"
<strong>... | Hash Table; String; Sliding Window | C# | public class Solution {
public int LengthOfLongestSubstring(string s) {
int n = s.Length;
int ans = 0;
var cnt = new int[128];
for (int l = 0, r = 0; r < n; ++r) {
++cnt[s[r]];
while (cnt[s[r]] > 1) {
--cnt[s[l++]];
}
an... |
3 | Longest Substring Without Repeating Characters | Medium | <p>Given a string <code>s</code>, find the length of the <strong>longest</strong> <span data-keyword="substring-nonempty"><strong>substring</strong></span> without duplicate characters.</p>
<p> </p>
<p><strong class="example">Example 1:</strong></p>
<pre>
<strong>Input:</strong> s = "abcabcbb"
<strong>... | Hash Table; String; Sliding Window | Go | func lengthOfLongestSubstring(s string) (ans int) {
cnt := [128]int{}
l := 0
for r, c := range s {
cnt[c]++
for cnt[c] > 1 {
cnt[s[l]]--
l++
}
ans = max(ans, r-l+1)
}
return
}
|
3 | Longest Substring Without Repeating Characters | Medium | <p>Given a string <code>s</code>, find the length of the <strong>longest</strong> <span data-keyword="substring-nonempty"><strong>substring</strong></span> without duplicate characters.</p>
<p> </p>
<p><strong class="example">Example 1:</strong></p>
<pre>
<strong>Input:</strong> s = "abcabcbb"
<strong>... | Hash Table; String; Sliding Window | Java | class Solution {
public int lengthOfLongestSubstring(String s) {
int[] cnt = new int[128];
int ans = 0, n = s.length();
for (int l = 0, r = 0; r < n; ++r) {
char c = s.charAt(r);
++cnt[c];
while (cnt[c] > 1) {
--cnt[s.charAt(l++)];
... |
3 | Longest Substring Without Repeating Characters | Medium | <p>Given a string <code>s</code>, find the length of the <strong>longest</strong> <span data-keyword="substring-nonempty"><strong>substring</strong></span> without duplicate characters.</p>
<p> </p>
<p><strong class="example">Example 1:</strong></p>
<pre>
<strong>Input:</strong> s = "abcabcbb"
<strong>... | Hash Table; String; Sliding Window | JavaScript | /**
* @param {string} s
* @return {number}
*/
var lengthOfLongestSubstring = function (s) {
let ans = 0;
const n = s.length;
const cnt = new Map();
for (let l = 0, r = 0; r < n; ++r) {
cnt.set(s[r], (cnt.get(s[r]) || 0) + 1);
while (cnt.get(s[r]) > 1) {
cnt.set(s[l], cnt.g... |
3 | Longest Substring Without Repeating Characters | Medium | <p>Given a string <code>s</code>, find the length of the <strong>longest</strong> <span data-keyword="substring-nonempty"><strong>substring</strong></span> without duplicate characters.</p>
<p> </p>
<p><strong class="example">Example 1:</strong></p>
<pre>
<strong>Input:</strong> s = "abcabcbb"
<strong>... | Hash Table; String; Sliding Window | Kotlin | class Solution {
fun lengthOfLongestSubstring(s: String): Int {
val n = s.length
var ans = 0
val cnt = IntArray(128)
var l = 0
for (r in 0 until n) {
cnt[s[r].toInt()]++
while (cnt[s[r].toInt()] > 1) {
cnt[s[l].toInt()]--
... |
3 | Longest Substring Without Repeating Characters | Medium | <p>Given a string <code>s</code>, find the length of the <strong>longest</strong> <span data-keyword="substring-nonempty"><strong>substring</strong></span> without duplicate characters.</p>
<p> </p>
<p><strong class="example">Example 1:</strong></p>
<pre>
<strong>Input:</strong> s = "abcabcbb"
<strong>... | Hash Table; String; Sliding Window | PHP | class Solution {
function lengthOfLongestSubstring($s) {
$n = strlen($s);
$ans = 0;
$cnt = array_fill(0, 128, 0);
$l = 0;
for ($r = 0; $r < $n; ++$r) {
$cnt[ord($s[$r])]++;
while ($cnt[ord($s[$r])] > 1) {
$cnt[ord($s[$l])]--;
... |
3 | Longest Substring Without Repeating Characters | Medium | <p>Given a string <code>s</code>, find the length of the <strong>longest</strong> <span data-keyword="substring-nonempty"><strong>substring</strong></span> without duplicate characters.</p>
<p> </p>
<p><strong class="example">Example 1:</strong></p>
<pre>
<strong>Input:</strong> s = "abcabcbb"
<strong>... | Hash Table; String; Sliding Window | Python | class Solution:
def lengthOfLongestSubstring(self, s: str) -> int:
cnt = Counter()
ans = l = 0
for r, c in enumerate(s):
cnt[c] += 1
while cnt[c] > 1:
cnt[s[l]] -= 1
l += 1
ans = max(ans, r - l + 1)
return ans
|
3 | Longest Substring Without Repeating Characters | Medium | <p>Given a string <code>s</code>, find the length of the <strong>longest</strong> <span data-keyword="substring-nonempty"><strong>substring</strong></span> without duplicate characters.</p>
<p> </p>
<p><strong class="example">Example 1:</strong></p>
<pre>
<strong>Input:</strong> s = "abcabcbb"
<strong>... | Hash Table; String; Sliding Window | Rust | impl Solution {
pub fn length_of_longest_substring(s: String) -> i32 {
let mut cnt = [0; 128];
let mut ans = 0;
let mut l = 0;
let chars: Vec<char> = s.chars().collect();
let n = chars.len();
for (r, &c) in chars.iter().enumerate() {
cnt[c as usize] += 1;
... |
3 | Longest Substring Without Repeating Characters | Medium | <p>Given a string <code>s</code>, find the length of the <strong>longest</strong> <span data-keyword="substring-nonempty"><strong>substring</strong></span> without duplicate characters.</p>
<p> </p>
<p><strong class="example">Example 1:</strong></p>
<pre>
<strong>Input:</strong> s = "abcabcbb"
<strong>... | Hash Table; String; Sliding Window | Swift | class Solution {
func lengthOfLongestSubstring(_ s: String) -> Int {
let n = s.count
var ans = 0
var cnt = [Int](repeating: 0, count: 128)
var l = 0
let sArray = Array(s)
for r in 0..<n {
cnt[Int(sArray[r].asciiValue!)] += 1
while cnt[Int(sArra... |
3 | Longest Substring Without Repeating Characters | Medium | <p>Given a string <code>s</code>, find the length of the <strong>longest</strong> <span data-keyword="substring-nonempty"><strong>substring</strong></span> without duplicate characters.</p>
<p> </p>
<p><strong class="example">Example 1:</strong></p>
<pre>
<strong>Input:</strong> s = "abcabcbb"
<strong>... | Hash Table; String; Sliding Window | TypeScript | function lengthOfLongestSubstring(s: string): number {
let ans = 0;
const cnt = new Map<string, number>();
const n = s.length;
for (let l = 0, r = 0; r < n; ++r) {
cnt.set(s[r], (cnt.get(s[r]) || 0) + 1);
while (cnt.get(s[r])! > 1) {
cnt.set(s[l], cnt.get(s[l])! - 1);
... |
4 | Median of Two Sorted Arrays | Hard | <p>Given two sorted arrays <code>nums1</code> and <code>nums2</code> of size <code>m</code> and <code>n</code> respectively, return <strong>the median</strong> of the two sorted arrays.</p>
<p>The overall run time complexity should be <code>O(log (m+n))</code>.</p>
<p> </p>
<p><strong class="example">Example 1:<... | Array; Binary Search; Divide and Conquer | C | int findKth(int* nums1, int m, int i, int* nums2, int n, int j, int k) {
if (i >= m)
return nums2[j + k - 1];
if (j >= n)
return nums1[i + k - 1];
if (k == 1)
return nums1[i] < nums2[j] ? nums1[i] : nums2[j];
int p = k / 2;
int x = (i + p - 1 < m) ? nums1[i + p - 1] : INT_M... |
4 | Median of Two Sorted Arrays | Hard | <p>Given two sorted arrays <code>nums1</code> and <code>nums2</code> of size <code>m</code> and <code>n</code> respectively, return <strong>the median</strong> of the two sorted arrays.</p>
<p>The overall run time complexity should be <code>O(log (m+n))</code>.</p>
<p> </p>
<p><strong class="example">Example 1:<... | Array; Binary Search; Divide and Conquer | C++ | class Solution {
public:
double findMedianSortedArrays(vector<int>& nums1, vector<int>& nums2) {
int m = nums1.size(), n = nums2.size();
function<int(int, int, int)> f = [&](int i, int j, int k) {
if (i >= m) {
return nums2[j + k - 1];
}
if (j >= n... |
4 | Median of Two Sorted Arrays | Hard | <p>Given two sorted arrays <code>nums1</code> and <code>nums2</code> of size <code>m</code> and <code>n</code> respectively, return <strong>the median</strong> of the two sorted arrays.</p>
<p>The overall run time complexity should be <code>O(log (m+n))</code>.</p>
<p> </p>
<p><strong class="example">Example 1:<... | Array; Binary Search; Divide and Conquer | C# | public class Solution {
private int m;
private int n;
private int[] nums1;
private int[] nums2;
public double FindMedianSortedArrays(int[] nums1, int[] nums2) {
m = nums1.Length;
n = nums2.Length;
this.nums1 = nums1;
this.nums2 = nums2;
int a = f(0, 0, (m + n... |
4 | Median of Two Sorted Arrays | Hard | <p>Given two sorted arrays <code>nums1</code> and <code>nums2</code> of size <code>m</code> and <code>n</code> respectively, return <strong>the median</strong> of the two sorted arrays.</p>
<p>The overall run time complexity should be <code>O(log (m+n))</code>.</p>
<p> </p>
<p><strong class="example">Example 1:<... | Array; Binary Search; Divide and Conquer | Go | func findMedianSortedArrays(nums1 []int, nums2 []int) float64 {
m, n := len(nums1), len(nums2)
var f func(i, j, k int) int
f = func(i, j, k int) int {
if i >= m {
return nums2[j+k-1]
}
if j >= n {
return nums1[i+k-1]
}
if k == 1 {
return min(nums1[i], nums2[j])
}
p := k / 2
x, y := 1<<30, 1<... |
4 | Median of Two Sorted Arrays | Hard | <p>Given two sorted arrays <code>nums1</code> and <code>nums2</code> of size <code>m</code> and <code>n</code> respectively, return <strong>the median</strong> of the two sorted arrays.</p>
<p>The overall run time complexity should be <code>O(log (m+n))</code>.</p>
<p> </p>
<p><strong class="example">Example 1:<... | Array; Binary Search; Divide and Conquer | Java | class Solution {
private int m;
private int n;
private int[] nums1;
private int[] nums2;
public double findMedianSortedArrays(int[] nums1, int[] nums2) {
m = nums1.length;
n = nums2.length;
this.nums1 = nums1;
this.nums2 = nums2;
int a = f(0, 0, (m + n + 1) /... |
4 | Median of Two Sorted Arrays | Hard | <p>Given two sorted arrays <code>nums1</code> and <code>nums2</code> of size <code>m</code> and <code>n</code> respectively, return <strong>the median</strong> of the two sorted arrays.</p>
<p>The overall run time complexity should be <code>O(log (m+n))</code>.</p>
<p> </p>
<p><strong class="example">Example 1:<... | Array; Binary Search; Divide and Conquer | JavaScript | /**
* @param {number[]} nums1
* @param {number[]} nums2
* @return {number}
*/
var findMedianSortedArrays = function (nums1, nums2) {
const m = nums1.length;
const n = nums2.length;
const f = (i, j, k) => {
if (i >= m) {
return nums2[j + k - 1];
}
if (j >= n) {
... |
4 | Median of Two Sorted Arrays | Hard | <p>Given two sorted arrays <code>nums1</code> and <code>nums2</code> of size <code>m</code> and <code>n</code> respectively, return <strong>the median</strong> of the two sorted arrays.</p>
<p>The overall run time complexity should be <code>O(log (m+n))</code>.</p>
<p> </p>
<p><strong class="example">Example 1:<... | Array; Binary Search; Divide and Conquer | Nim | import std/[algorithm, sequtils]
proc medianOfTwoSortedArrays(nums1: seq[int], nums2: seq[int]): float =
var
fullList: seq[int] = concat(nums1, nums2)
value: int = fullList.len div 2
fullList.sort()
if fullList.len mod 2 == 0:
result = (fullList[value - 1] + fullList[value]) / 2
else:
result ... |
4 | Median of Two Sorted Arrays | Hard | <p>Given two sorted arrays <code>nums1</code> and <code>nums2</code> of size <code>m</code> and <code>n</code> respectively, return <strong>the median</strong> of the two sorted arrays.</p>
<p>The overall run time complexity should be <code>O(log (m+n))</code>.</p>
<p> </p>
<p><strong class="example">Example 1:<... | Array; Binary Search; Divide and Conquer | PHP | class Solution {
/**
* @param int[] $nums1
* @param int[] $nums2
* @return float
*/
function findMedianSortedArrays($nums1, $nums2) {
$arr = array_merge($nums1, $nums2);
sort($arr);
$cnt_arr = count($arr);
if ($cnt_arr % 2) {
return $arr[$cnt_arr... |
4 | Median of Two Sorted Arrays | Hard | <p>Given two sorted arrays <code>nums1</code> and <code>nums2</code> of size <code>m</code> and <code>n</code> respectively, return <strong>the median</strong> of the two sorted arrays.</p>
<p>The overall run time complexity should be <code>O(log (m+n))</code>.</p>
<p> </p>
<p><strong class="example">Example 1:<... | Array; Binary Search; Divide and Conquer | Python | class Solution:
def findMedianSortedArrays(self, nums1: List[int], nums2: List[int]) -> float:
def f(i: int, j: int, k: int) -> int:
if i >= m:
return nums2[j + k - 1]
if j >= n:
return nums1[i + k - 1]
if k == 1:
return min... |
4 | Median of Two Sorted Arrays | Hard | <p>Given two sorted arrays <code>nums1</code> and <code>nums2</code> of size <code>m</code> and <code>n</code> respectively, return <strong>the median</strong> of the two sorted arrays.</p>
<p>The overall run time complexity should be <code>O(log (m+n))</code>.</p>
<p> </p>
<p><strong class="example">Example 1:<... | Array; Binary Search; Divide and Conquer | TypeScript | function findMedianSortedArrays(nums1: number[], nums2: number[]): number {
const m = nums1.length;
const n = nums2.length;
const f = (i: number, j: number, k: number): number => {
if (i >= m) {
return nums2[j + k - 1];
}
if (j >= n) {
return nums1[i + k - 1];... |
5 | Longest Palindromic Substring | Medium | <p>Given a string <code>s</code>, return <em>the longest</em> <span data-keyword="palindromic-string"><em>palindromic</em></span> <span data-keyword="substring-nonempty"><em>substring</em></span> in <code>s</code>.</p>
<p> </p>
<p><strong class="example">Example 1:</strong></p>
<pre>
<strong>Input:</strong> s = ... | Two Pointers; String; Dynamic Programming | C | char* longestPalindrome(char* s) {
int n = strlen(s);
bool** f = (bool**) malloc(n * sizeof(bool*));
for (int i = 0; i < n; ++i) {
f[i] = (bool*) malloc(n * sizeof(bool));
for (int j = 0; j < n; ++j) {
f[i][j] = true;
}
}
int k = 0, mx = 1;
for (int i = n - 2;... |
5 | Longest Palindromic Substring | Medium | <p>Given a string <code>s</code>, return <em>the longest</em> <span data-keyword="palindromic-string"><em>palindromic</em></span> <span data-keyword="substring-nonempty"><em>substring</em></span> in <code>s</code>.</p>
<p> </p>
<p><strong class="example">Example 1:</strong></p>
<pre>
<strong>Input:</strong> s = ... | Two Pointers; String; Dynamic Programming | C++ | class Solution {
public:
string longestPalindrome(string s) {
int n = s.size();
vector<vector<bool>> f(n, vector<bool>(n, true));
int k = 0, mx = 1;
for (int i = n - 2; ~i; --i) {
for (int j = i + 1; j < n; ++j) {
f[i][j] = false;
if (s[i] ... |
5 | Longest Palindromic Substring | Medium | <p>Given a string <code>s</code>, return <em>the longest</em> <span data-keyword="palindromic-string"><em>palindromic</em></span> <span data-keyword="substring-nonempty"><em>substring</em></span> in <code>s</code>.</p>
<p> </p>
<p><strong class="example">Example 1:</strong></p>
<pre>
<strong>Input:</strong> s = ... | Two Pointers; String; Dynamic Programming | C# | public class Solution {
public string LongestPalindrome(string s) {
int n = s.Length;
bool[,] f = new bool[n, n];
for (int i = 0; i < n; i++) {
for (int j = 0; j < n; ++j) {
f[i, j] = true;
}
}
int k = 0, mx = 1;
for (int i = n ... |
5 | Longest Palindromic Substring | Medium | <p>Given a string <code>s</code>, return <em>the longest</em> <span data-keyword="palindromic-string"><em>palindromic</em></span> <span data-keyword="substring-nonempty"><em>substring</em></span> in <code>s</code>.</p>
<p> </p>
<p><strong class="example">Example 1:</strong></p>
<pre>
<strong>Input:</strong> s = ... | Two Pointers; String; Dynamic Programming | Go | func longestPalindrome(s string) string {
n := len(s)
f := make([][]bool, n)
for i := range f {
f[i] = make([]bool, n)
for j := range f[i] {
f[i][j] = true
}
}
k, mx := 0, 1
for i := n - 2; i >= 0; i-- {
for j := i + 1; j < n; j++ {
f[i][j] = false
if s[i] == s[j] {
f[i][j] = f[i+1][j-1]
... |
5 | Longest Palindromic Substring | Medium | <p>Given a string <code>s</code>, return <em>the longest</em> <span data-keyword="palindromic-string"><em>palindromic</em></span> <span data-keyword="substring-nonempty"><em>substring</em></span> in <code>s</code>.</p>
<p> </p>
<p><strong class="example">Example 1:</strong></p>
<pre>
<strong>Input:</strong> s = ... | Two Pointers; String; Dynamic Programming | Java | class Solution {
public String longestPalindrome(String s) {
int n = s.length();
boolean[][] f = new boolean[n][n];
for (var g : f) {
Arrays.fill(g, true);
}
int k = 0, mx = 1;
for (int i = n - 2; i >= 0; --i) {
for (int j = i + 1; j < n; ++j) ... |
5 | Longest Palindromic Substring | Medium | <p>Given a string <code>s</code>, return <em>the longest</em> <span data-keyword="palindromic-string"><em>palindromic</em></span> <span data-keyword="substring-nonempty"><em>substring</em></span> in <code>s</code>.</p>
<p> </p>
<p><strong class="example">Example 1:</strong></p>
<pre>
<strong>Input:</strong> s = ... | Two Pointers; String; Dynamic Programming | JavaScript | /**
* @param {string} s
* @return {string}
*/
var longestPalindrome = function (s) {
const n = s.length;
const f = Array(n)
.fill(0)
.map(() => Array(n).fill(true));
let k = 0;
let mx = 1;
for (let i = n - 2; i >= 0; --i) {
for (let j = i + 1; j < n; ++j) {
f[i... |
5 | Longest Palindromic Substring | Medium | <p>Given a string <code>s</code>, return <em>the longest</em> <span data-keyword="palindromic-string"><em>palindromic</em></span> <span data-keyword="substring-nonempty"><em>substring</em></span> in <code>s</code>.</p>
<p> </p>
<p><strong class="example">Example 1:</strong></p>
<pre>
<strong>Input:</strong> s = ... | Two Pointers; String; Dynamic Programming | Nim | import std/sequtils
proc longestPalindrome(s: string): string =
let n: int = s.len()
var
dp = newSeqWith[bool](n, newSeqWith[bool](n, false))
start: int = 0
mx: int = 1
for j in 0 ..< n:
for i in 0 .. j:
if j - i < 2:
dp[i][j] = s[i] == s[j]
else:
dp[i][j] = dp[i + 1]... |
5 | Longest Palindromic Substring | Medium | <p>Given a string <code>s</code>, return <em>the longest</em> <span data-keyword="palindromic-string"><em>palindromic</em></span> <span data-keyword="substring-nonempty"><em>substring</em></span> in <code>s</code>.</p>
<p> </p>
<p><strong class="example">Example 1:</strong></p>
<pre>
<strong>Input:</strong> s = ... | Two Pointers; String; Dynamic Programming | PHP | class Solution {
/**
* @param string $s
* @return string
*/
function longestPalindrome($s) {
$start = 0;
$maxLength = 0;
for ($i = 0; $i < strlen($s); $i++) {
$len1 = $this->expandFromCenter($s, $i, $i);
$len2 = $this->expandFromCenter($s, $i, $i +... |
5 | Longest Palindromic Substring | Medium | <p>Given a string <code>s</code>, return <em>the longest</em> <span data-keyword="palindromic-string"><em>palindromic</em></span> <span data-keyword="substring-nonempty"><em>substring</em></span> in <code>s</code>.</p>
<p> </p>
<p><strong class="example">Example 1:</strong></p>
<pre>
<strong>Input:</strong> s = ... | Two Pointers; String; Dynamic Programming | Python | class Solution:
def longestPalindrome(self, s: str) -> str:
n = len(s)
f = [[True] * n for _ in range(n)]
k, mx = 0, 1
for i in range(n - 2, -1, -1):
for j in range(i + 1, n):
f[i][j] = False
if s[i] == s[j]:
f[i][j] = f... |
5 | Longest Palindromic Substring | Medium | <p>Given a string <code>s</code>, return <em>the longest</em> <span data-keyword="palindromic-string"><em>palindromic</em></span> <span data-keyword="substring-nonempty"><em>substring</em></span> in <code>s</code>.</p>
<p> </p>
<p><strong class="example">Example 1:</strong></p>
<pre>
<strong>Input:</strong> s = ... | Two Pointers; String; Dynamic Programming | Rust | impl Solution {
pub fn longest_palindrome(s: String) -> String {
let (n, mut ans) = (s.len(), &s[..1]);
let mut dp = vec![vec![false; n]; n];
let data: Vec<char> = s.chars().collect();
for end in 1..n {
for start in 0..=end {
if data[start] == data[end] {... |
5 | Longest Palindromic Substring | Medium | <p>Given a string <code>s</code>, return <em>the longest</em> <span data-keyword="palindromic-string"><em>palindromic</em></span> <span data-keyword="substring-nonempty"><em>substring</em></span> in <code>s</code>.</p>
<p> </p>
<p><strong class="example">Example 1:</strong></p>
<pre>
<strong>Input:</strong> s = ... | Two Pointers; String; Dynamic Programming | TypeScript | function longestPalindrome(s: string): string {
const n = s.length;
const f: boolean[][] = Array(n)
.fill(0)
.map(() => Array(n).fill(true));
let k = 0;
let mx = 1;
for (let i = n - 2; i >= 0; --i) {
for (let j = i + 1; j < n; ++j) {
f[i][j] = false;
i... |
6 | Zigzag Conversion | Medium | <p>The string <code>"PAYPALISHIRING"</code> is written in a zigzag pattern on a given number of rows like this: (you may want to display this pattern in a fixed font for better legibility)</p>
<pre>
P A H N
A P L S I I G
Y I R
</pre>
<p>And then read line by line: <code>"PAHNAPLSIIGYIR"<... | String | C | char* convert(char* s, int numRows) {
if (numRows == 1) {
return strdup(s);
}
int len = strlen(s);
char** g = (char**) malloc(numRows * sizeof(char*));
int* idx = (int*) malloc(numRows * sizeof(int));
for (int i = 0; i < numRows; ++i) {
g[i] = (char*) malloc((len + 1) * sizeof(c... |
6 | Zigzag Conversion | Medium | <p>The string <code>"PAYPALISHIRING"</code> is written in a zigzag pattern on a given number of rows like this: (you may want to display this pattern in a fixed font for better legibility)</p>
<pre>
P A H N
A P L S I I G
Y I R
</pre>
<p>And then read line by line: <code>"PAHNAPLSIIGYIR"<... | String | C++ | class Solution {
public:
string convert(string s, int numRows) {
if (numRows == 1) {
return s;
}
vector<string> g(numRows);
int i = 0, k = -1;
for (char c : s) {
g[i] += c;
if (i == 0 || i == numRows - 1) {
k = -k;
... |
6 | Zigzag Conversion | Medium | <p>The string <code>"PAYPALISHIRING"</code> is written in a zigzag pattern on a given number of rows like this: (you may want to display this pattern in a fixed font for better legibility)</p>
<pre>
P A H N
A P L S I I G
Y I R
</pre>
<p>And then read line by line: <code>"PAHNAPLSIIGYIR"<... | String | C# | public class Solution {
public string Convert(string s, int numRows) {
if (numRows == 1) {
return s;
}
int n = s.Length;
StringBuilder[] g = new StringBuilder[numRows];
for (int j = 0; j < numRows; ++j) {
g[j] = new StringBuilder();
}
i... |
6 | Zigzag Conversion | Medium | <p>The string <code>"PAYPALISHIRING"</code> is written in a zigzag pattern on a given number of rows like this: (you may want to display this pattern in a fixed font for better legibility)</p>
<pre>
P A H N
A P L S I I G
Y I R
</pre>
<p>And then read line by line: <code>"PAHNAPLSIIGYIR"<... | String | Go | func convert(s string, numRows int) string {
if numRows == 1 {
return s
}
g := make([][]byte, numRows)
i, k := 0, -1
for _, c := range s {
g[i] = append(g[i], byte(c))
if i == 0 || i == numRows-1 {
k = -k
}
i += k
}
return string(bytes.Join(g, nil))
} |
6 | Zigzag Conversion | Medium | <p>The string <code>"PAYPALISHIRING"</code> is written in a zigzag pattern on a given number of rows like this: (you may want to display this pattern in a fixed font for better legibility)</p>
<pre>
P A H N
A P L S I I G
Y I R
</pre>
<p>And then read line by line: <code>"PAHNAPLSIIGYIR"<... | String | Java | class Solution {
public String convert(String s, int numRows) {
if (numRows == 1) {
return s;
}
StringBuilder[] g = new StringBuilder[numRows];
Arrays.setAll(g, k -> new StringBuilder());
int i = 0, k = -1;
for (char c : s.toCharArray()) {
g[i]... |
6 | Zigzag Conversion | Medium | <p>The string <code>"PAYPALISHIRING"</code> is written in a zigzag pattern on a given number of rows like this: (you may want to display this pattern in a fixed font for better legibility)</p>
<pre>
P A H N
A P L S I I G
Y I R
</pre>
<p>And then read line by line: <code>"PAHNAPLSIIGYIR"<... | String | JavaScript | /**
* @param {string} s
* @param {number} numRows
* @return {string}
*/
var convert = function (s, numRows) {
if (numRows === 1) {
return s;
}
const g = new Array(numRows).fill(_).map(() => []);
let i = 0;
let k = -1;
for (const c of s) {
g[i].push(c);
if (i === 0 || ... |
6 | Zigzag Conversion | Medium | <p>The string <code>"PAYPALISHIRING"</code> is written in a zigzag pattern on a given number of rows like this: (you may want to display this pattern in a fixed font for better legibility)</p>
<pre>
P A H N
A P L S I I G
Y I R
</pre>
<p>And then read line by line: <code>"PAHNAPLSIIGYIR"<... | String | PHP | class Solution {
/**
* @param String $s
* @param Integer $numRows
* @return String
*/
function convert($s, $numRows) {
if ($numRows == 1) {
return $s;
}
$g = array_fill(0, $numRows, "");
$i = 0;
$k = -1;
$length = strlen($s);
... |
6 | Zigzag Conversion | Medium | <p>The string <code>"PAYPALISHIRING"</code> is written in a zigzag pattern on a given number of rows like this: (you may want to display this pattern in a fixed font for better legibility)</p>
<pre>
P A H N
A P L S I I G
Y I R
</pre>
<p>And then read line by line: <code>"PAHNAPLSIIGYIR"<... | String | Python | class Solution:
def convert(self, s: str, numRows: int) -> str:
if numRows == 1:
return s
g = [[] for _ in range(numRows)]
i, k = 0, -1
for c in s:
g[i].append(c)
if i == 0 or i == numRows - 1:
k = -k
i += k
retu... |
6 | Zigzag Conversion | Medium | <p>The string <code>"PAYPALISHIRING"</code> is written in a zigzag pattern on a given number of rows like this: (you may want to display this pattern in a fixed font for better legibility)</p>
<pre>
P A H N
A P L S I I G
Y I R
</pre>
<p>And then read line by line: <code>"PAHNAPLSIIGYIR"<... | String | Rust | impl Solution {
pub fn convert(s: String, num_rows: i32) -> String {
if num_rows == 1 {
return s;
}
let num_rows = num_rows as usize;
let mut g = vec![String::new(); num_rows];
let mut i = 0;
let mut k = -1;
for c in s.chars() {
g[i].... |
6 | Zigzag Conversion | Medium | <p>The string <code>"PAYPALISHIRING"</code> is written in a zigzag pattern on a given number of rows like this: (you may want to display this pattern in a fixed font for better legibility)</p>
<pre>
P A H N
A P L S I I G
Y I R
</pre>
<p>And then read line by line: <code>"PAHNAPLSIIGYIR"<... | String | TypeScript | function convert(s: string, numRows: number): string {
if (numRows === 1) {
return s;
}
const g: string[][] = new Array(numRows).fill(0).map(() => []);
let i = 0;
let k = -1;
for (const c of s) {
g[i].push(c);
if (i === numRows - 1 || i === 0) {
k = -k;
... |
7 | Reverse Integer | Medium | <p>Given a signed 32-bit integer <code>x</code>, return <code>x</code><em> with its digits reversed</em>. If reversing <code>x</code> causes the value to go outside the signed 32-bit integer range <code>[-2<sup>31</sup>, 2<sup>31</sup> - 1]</code>, then return <code>0</code>.</p>
<p><strong>Assume the environment does... | Math | C | int reverse(int x) {
int ans = 0;
for (; x != 0; x /= 10) {
if (ans > INT_MAX / 10 || ans < INT_MIN / 10) {
return 0;
}
ans = ans * 10 + x % 10;
}
return ans;
} |
7 | Reverse Integer | Medium | <p>Given a signed 32-bit integer <code>x</code>, return <code>x</code><em> with its digits reversed</em>. If reversing <code>x</code> causes the value to go outside the signed 32-bit integer range <code>[-2<sup>31</sup>, 2<sup>31</sup> - 1]</code>, then return <code>0</code>.</p>
<p><strong>Assume the environment does... | Math | C++ | class Solution {
public:
int reverse(int x) {
int ans = 0;
for (; x; x /= 10) {
if (ans < INT_MIN / 10 || ans > INT_MAX / 10) {
return 0;
}
ans = ans * 10 + x % 10;
}
return ans;
}
}; |
7 | Reverse Integer | Medium | <p>Given a signed 32-bit integer <code>x</code>, return <code>x</code><em> with its digits reversed</em>. If reversing <code>x</code> causes the value to go outside the signed 32-bit integer range <code>[-2<sup>31</sup>, 2<sup>31</sup> - 1]</code>, then return <code>0</code>.</p>
<p><strong>Assume the environment does... | Math | C# | public class Solution {
public int Reverse(int x) {
int ans = 0;
for (; x != 0; x /= 10) {
if (ans < int.MinValue / 10 || ans > int.MaxValue / 10) {
return 0;
}
ans = ans * 10 + x % 10;
}
return ans;
}
}
|
7 | Reverse Integer | Medium | <p>Given a signed 32-bit integer <code>x</code>, return <code>x</code><em> with its digits reversed</em>. If reversing <code>x</code> causes the value to go outside the signed 32-bit integer range <code>[-2<sup>31</sup>, 2<sup>31</sup> - 1]</code>, then return <code>0</code>.</p>
<p><strong>Assume the environment does... | Math | Go | func reverse(x int) (ans int) {
for ; x != 0; x /= 10 {
if ans < math.MinInt32/10 || ans > math.MaxInt32/10 {
return 0
}
ans = ans*10 + x%10
}
return
} |
7 | Reverse Integer | Medium | <p>Given a signed 32-bit integer <code>x</code>, return <code>x</code><em> with its digits reversed</em>. If reversing <code>x</code> causes the value to go outside the signed 32-bit integer range <code>[-2<sup>31</sup>, 2<sup>31</sup> - 1]</code>, then return <code>0</code>.</p>
<p><strong>Assume the environment does... | Math | Java | class Solution {
public int reverse(int x) {
int ans = 0;
for (; x != 0; x /= 10) {
if (ans < Integer.MIN_VALUE / 10 || ans > Integer.MAX_VALUE / 10) {
return 0;
}
ans = ans * 10 + x % 10;
}
return ans;
}
} |
7 | Reverse Integer | Medium | <p>Given a signed 32-bit integer <code>x</code>, return <code>x</code><em> with its digits reversed</em>. If reversing <code>x</code> causes the value to go outside the signed 32-bit integer range <code>[-2<sup>31</sup>, 2<sup>31</sup> - 1]</code>, then return <code>0</code>.</p>
<p><strong>Assume the environment does... | Math | JavaScript | /**
* @param {number} x
* @return {number}
*/
var reverse = function (x) {
const mi = -(2 ** 31);
const mx = 2 ** 31 - 1;
let ans = 0;
for (; x != 0; x = ~~(x / 10)) {
if (ans < ~~(mi / 10) || ans > ~~(mx / 10)) {
return 0;
}
ans = ans * 10 + (x % 10);
}
re... |
7 | Reverse Integer | Medium | <p>Given a signed 32-bit integer <code>x</code>, return <code>x</code><em> with its digits reversed</em>. If reversing <code>x</code> causes the value to go outside the signed 32-bit integer range <code>[-2<sup>31</sup>, 2<sup>31</sup> - 1]</code>, then return <code>0</code>.</p>
<p><strong>Assume the environment does... | Math | PHP | class Solution {
/**
* @param int $x
* @return int
*/
function reverse($x) {
$isNegative = $x < 0;
$x = abs($x);
$reversed = 0;
while ($x > 0) {
$reversed = $reversed * 10 + ($x % 10);
$x = (int) ($x / 10);
}
if ($isNegat... |
7 | Reverse Integer | Medium | <p>Given a signed 32-bit integer <code>x</code>, return <code>x</code><em> with its digits reversed</em>. If reversing <code>x</code> causes the value to go outside the signed 32-bit integer range <code>[-2<sup>31</sup>, 2<sup>31</sup> - 1]</code>, then return <code>0</code>.</p>
<p><strong>Assume the environment does... | Math | Python | class Solution:
def reverse(self, x: int) -> int:
ans = 0
mi, mx = -(2**31), 2**31 - 1
while x:
if ans < mi // 10 + 1 or ans > mx // 10:
return 0
y = x % 10
if x < 0 and y > 0:
y -= 10
ans = ans * 10 + y
... |
7 | Reverse Integer | Medium | <p>Given a signed 32-bit integer <code>x</code>, return <code>x</code><em> with its digits reversed</em>. If reversing <code>x</code> causes the value to go outside the signed 32-bit integer range <code>[-2<sup>31</sup>, 2<sup>31</sup> - 1]</code>, then return <code>0</code>.</p>
<p><strong>Assume the environment does... | Math | Rust | impl Solution {
pub fn reverse(mut x: i32) -> i32 {
let is_minus = x < 0;
match x
.abs()
.to_string()
.chars()
.rev()
.collect::<String>()
.parse::<i32>()
{
Ok(x) => x * (if is_minus { -1 } else { 1 }),
... |
8 | String to Integer (atoi) | Medium | <p>Implement the <code>myAtoi(string s)</code> function, which converts a string to a 32-bit signed integer.</p>
<p>The algorithm for <code>myAtoi(string s)</code> is as follows:</p>
<ol>
<li><strong>Whitespace</strong>: Ignore any leading whitespace (<code>" "</code>).</li>
<li><strong>Signedness</strong... | String | C | int myAtoi(char* s) {
int i = 0;
while (s[i] == ' ') {
i++;
}
int sign = 1;
if (s[i] == '-' || s[i] == '+') {
sign = (s[i] == '-') ? -1 : 1;
i++;
}
int res = 0;
while (isdigit(s[i])) {
int digit = s[i] - '0';
if (res > INT_MAX / 10 || (res == IN... |
8 | String to Integer (atoi) | Medium | <p>Implement the <code>myAtoi(string s)</code> function, which converts a string to a 32-bit signed integer.</p>
<p>The algorithm for <code>myAtoi(string s)</code> is as follows:</p>
<ol>
<li><strong>Whitespace</strong>: Ignore any leading whitespace (<code>" "</code>).</li>
<li><strong>Signedness</strong... | String | C++ | class Solution {
public:
int myAtoi(string s) {
int i = 0, n = s.size();
while (i < n && s[i] == ' ')
++i;
int sign = 1;
if (i < n && (s[i] == '-' || s[i] == '+')) {
sign = s[i] == '-' ? -1 : 1;
++i;
}
int res = 0;
while (... |
8 | String to Integer (atoi) | Medium | <p>Implement the <code>myAtoi(string s)</code> function, which converts a string to a 32-bit signed integer.</p>
<p>The algorithm for <code>myAtoi(string s)</code> is as follows:</p>
<ol>
<li><strong>Whitespace</strong>: Ignore any leading whitespace (<code>" "</code>).</li>
<li><strong>Signedness</strong... | String | C# | // https://leetcode.com/problems/string-to-integer-atoi/
public partial class Solution
{
public int MyAtoi(string str)
{
int i = 0;
long result = 0;
bool minus = false;
while (i < str.Length && char.IsWhiteSpace(str[i]))
{
++i;
}
if (i < str.... |
8 | String to Integer (atoi) | Medium | <p>Implement the <code>myAtoi(string s)</code> function, which converts a string to a 32-bit signed integer.</p>
<p>The algorithm for <code>myAtoi(string s)</code> is as follows:</p>
<ol>
<li><strong>Whitespace</strong>: Ignore any leading whitespace (<code>" "</code>).</li>
<li><strong>Signedness</strong... | String | Go | func myAtoi(s string) int {
i, n := 0, len(s)
num := 0
for i < n && s[i] == ' ' {
i++
}
if i == n {
return 0
}
sign := 1
if s[i] == '-' {
sign = -1
i++
} else if s[i] == '+' {
i++
}
for i < n && s[i] >= '0' && s[i] <= '9' {
num = num*10 + int(s[i]-'0')
i++
if num > math.MaxInt32 {
break... |
8 | String to Integer (atoi) | Medium | <p>Implement the <code>myAtoi(string s)</code> function, which converts a string to a 32-bit signed integer.</p>
<p>The algorithm for <code>myAtoi(string s)</code> is as follows:</p>
<ol>
<li><strong>Whitespace</strong>: Ignore any leading whitespace (<code>" "</code>).</li>
<li><strong>Signedness</strong... | String | Java | class Solution {
public int myAtoi(String s) {
if (s == null) return 0;
int n = s.length();
if (n == 0) return 0;
int i = 0;
while (s.charAt(i) == ' ') {
// 仅包含空格
if (++i == n) return 0;
}
int sign = 1;
if (s.charAt(i) == '-') s... |
8 | String to Integer (atoi) | Medium | <p>Implement the <code>myAtoi(string s)</code> function, which converts a string to a 32-bit signed integer.</p>
<p>The algorithm for <code>myAtoi(string s)</code> is as follows:</p>
<ol>
<li><strong>Whitespace</strong>: Ignore any leading whitespace (<code>" "</code>).</li>
<li><strong>Signedness</strong... | String | JavaScript | const myAtoi = function (str) {
str = str.trim();
if (!str) return 0;
let isPositive = 1;
let i = 0,
ans = 0;
if (str[i] === '+') {
isPositive = 1;
i++;
} else if (str[i] === '-') {
isPositive = 0;
i++;
}
for (; i < str.length; i++) {
let t... |
8 | String to Integer (atoi) | Medium | <p>Implement the <code>myAtoi(string s)</code> function, which converts a string to a 32-bit signed integer.</p>
<p>The algorithm for <code>myAtoi(string s)</code> is as follows:</p>
<ol>
<li><strong>Whitespace</strong>: Ignore any leading whitespace (<code>" "</code>).</li>
<li><strong>Signedness</strong... | String | PHP | class Solution {
/**
* @param string $s
* @return int
*/
function myAtoi($s) {
$s = str_replace('e', 'x', $s);
if (intval($s) < pow(-2, 31)) {
return -2147483648;
}
if (intval($s) > pow(2, 31) - 1) {
return 2147483647;
}
ret... |
8 | String to Integer (atoi) | Medium | <p>Implement the <code>myAtoi(string s)</code> function, which converts a string to a 32-bit signed integer.</p>
<p>The algorithm for <code>myAtoi(string s)</code> is as follows:</p>
<ol>
<li><strong>Whitespace</strong>: Ignore any leading whitespace (<code>" "</code>).</li>
<li><strong>Signedness</strong... | String | Python | class Solution:
def myAtoi(self, s: str) -> int:
if not s:
return 0
n = len(s)
if n == 0:
return 0
i = 0
while s[i] == ' ':
i += 1
# 仅包含空格
if i == n:
return 0
sign = -1 if s[i] == '-' else 1
... |
9 | Palindrome Number | Easy | <p>Given an integer <code>x</code>, return <code>true</code><em> if </em><code>x</code><em> is a </em><span data-keyword="palindrome-integer"><em><strong>palindrome</strong></em></span><em>, and </em><code>false</code><em> otherwise</em>.</p>
<p> </p>
<p><strong class="example">Example 1:</strong></p>
<pre>
<str... | Math | C | bool isPalindrome(int x) {
if (x < 0 || (x != 0 && x % 10 == 0)) {
return false;
}
int y = 0;
while (y < x) {
y = y * 10 + x % 10;
x /= 10;
}
return (x == y || x == y / 10);
}
|
9 | Palindrome Number | Easy | <p>Given an integer <code>x</code>, return <code>true</code><em> if </em><code>x</code><em> is a </em><span data-keyword="palindrome-integer"><em><strong>palindrome</strong></em></span><em>, and </em><code>false</code><em> otherwise</em>.</p>
<p> </p>
<p><strong class="example">Example 1:</strong></p>
<pre>
<str... | Math | C++ | class Solution {
public:
bool isPalindrome(int x) {
if (x < 0 || (x && x % 10 == 0)) {
return false;
}
int y = 0;
for (; y < x; x /= 10) {
y = y * 10 + x % 10;
}
return x == y || x == y / 10;
}
}; |
9 | Palindrome Number | Easy | <p>Given an integer <code>x</code>, return <code>true</code><em> if </em><code>x</code><em> is a </em><span data-keyword="palindrome-integer"><em><strong>palindrome</strong></em></span><em>, and </em><code>false</code><em> otherwise</em>.</p>
<p> </p>
<p><strong class="example">Example 1:</strong></p>
<pre>
<str... | Math | C# | public class Solution {
public bool IsPalindrome(int x) {
if (x < 0 || (x > 0 && x % 10 == 0)) {
return false;
}
int y = 0;
for (; y < x; x /= 10) {
y = y * 10 + x % 10;
}
return x == y || x == y / 10;
}
} |
9 | Palindrome Number | Easy | <p>Given an integer <code>x</code>, return <code>true</code><em> if </em><code>x</code><em> is a </em><span data-keyword="palindrome-integer"><em><strong>palindrome</strong></em></span><em>, and </em><code>false</code><em> otherwise</em>.</p>
<p> </p>
<p><strong class="example">Example 1:</strong></p>
<pre>
<str... | Math | Go | func isPalindrome(x int) bool {
if x < 0 || (x > 0 && x%10 == 0) {
return false
}
y := 0
for ; y < x; x /= 10 {
y = y*10 + x%10
}
return x == y || x == y/10
} |
9 | Palindrome Number | Easy | <p>Given an integer <code>x</code>, return <code>true</code><em> if </em><code>x</code><em> is a </em><span data-keyword="palindrome-integer"><em><strong>palindrome</strong></em></span><em>, and </em><code>false</code><em> otherwise</em>.</p>
<p> </p>
<p><strong class="example">Example 1:</strong></p>
<pre>
<str... | Math | Java | class Solution {
public boolean isPalindrome(int x) {
if (x < 0 || (x > 0 && x % 10 == 0)) {
return false;
}
int y = 0;
for (; y < x; x /= 10) {
y = y * 10 + x % 10;
}
return x == y || x == y / 10;
}
} |
9 | Palindrome Number | Easy | <p>Given an integer <code>x</code>, return <code>true</code><em> if </em><code>x</code><em> is a </em><span data-keyword="palindrome-integer"><em><strong>palindrome</strong></em></span><em>, and </em><code>false</code><em> otherwise</em>.</p>
<p> </p>
<p><strong class="example">Example 1:</strong></p>
<pre>
<str... | Math | JavaScript | /**
* @param {number} x
* @return {boolean}
*/
var isPalindrome = function (x) {
if (x < 0 || (x > 0 && x % 10 === 0)) {
return false;
}
let y = 0;
for (; y < x; x = ~~(x / 10)) {
y = y * 10 + (x % 10);
}
return x === y || x === ~~(y / 10);
};
|
9 | Palindrome Number | Easy | <p>Given an integer <code>x</code>, return <code>true</code><em> if </em><code>x</code><em> is a </em><span data-keyword="palindrome-integer"><em><strong>palindrome</strong></em></span><em>, and </em><code>false</code><em> otherwise</em>.</p>
<p> </p>
<p><strong class="example">Example 1:</strong></p>
<pre>
<str... | Math | PHP | class Solution {
/**
* @param Integer $x
* @return Boolean
*/
function isPalindrome($x) {
if ($x < 0 || ($x && $x % 10 == 0)) {
return false;
}
$y = 0;
while ($x > $y) {
$y = $y * 10 + ($x % 10);
$x = (int) ($x / 10);
}
... |
9 | Palindrome Number | Easy | <p>Given an integer <code>x</code>, return <code>true</code><em> if </em><code>x</code><em> is a </em><span data-keyword="palindrome-integer"><em><strong>palindrome</strong></em></span><em>, and </em><code>false</code><em> otherwise</em>.</p>
<p> </p>
<p><strong class="example">Example 1:</strong></p>
<pre>
<str... | Math | Python | class Solution:
def isPalindrome(self, x: int) -> bool:
if x < 0 or (x and x % 10 == 0):
return False
y = 0
while y < x:
y = y * 10 + x % 10
x //= 10
return x in (y, y // 10)
|
9 | Palindrome Number | Easy | <p>Given an integer <code>x</code>, return <code>true</code><em> if </em><code>x</code><em> is a </em><span data-keyword="palindrome-integer"><em><strong>palindrome</strong></em></span><em>, and </em><code>false</code><em> otherwise</em>.</p>
<p> </p>
<p><strong class="example">Example 1:</strong></p>
<pre>
<str... | Math | Rust | impl Solution {
pub fn is_palindrome(mut x: i32) -> bool {
if x < 0 || (x != 0 && x % 10 == 0) {
return false;
}
let mut y = 0;
while x > y {
y = y * 10 + x % 10;
x /= 10;
}
x == y || x == y / 10
}
}
|
9 | Palindrome Number | Easy | <p>Given an integer <code>x</code>, return <code>true</code><em> if </em><code>x</code><em> is a </em><span data-keyword="palindrome-integer"><em><strong>palindrome</strong></em></span><em>, and </em><code>false</code><em> otherwise</em>.</p>
<p> </p>
<p><strong class="example">Example 1:</strong></p>
<pre>
<str... | Math | TypeScript | function isPalindrome(x: number): boolean {
if (x < 0 || (x > 0 && x % 10 === 0)) {
return false;
}
let y = 0;
for (; y < x; x = ~~(x / 10)) {
y = y * 10 + (x % 10);
}
return x === y || x === ~~(y / 10);
}
|
10 | Regular Expression Matching | Hard | <p>Given an input string <code>s</code> and a pattern <code>p</code>, implement regular expression matching with support for <code>'.'</code> and <code>'*'</code> where:</p>
<ul>
<li><code>'.'</code> Matches any single character.</li>
<li><code>'*'</code> Matches zero or more... | Recursion; String; Dynamic Programming | C | #define MAX_LEN 1000
char *ss, *pp;
int m, n;
int f[MAX_LEN + 1][MAX_LEN + 1];
bool dfs(int i, int j) {
if (j >= n) {
return i == m;
}
if (f[i][j] != 0) {
return f[i][j] == 1;
}
int res = -1;
if (j + 1 < n && pp[j + 1] == '*') {
if (dfs(i, j + 2) || (i < m && (ss[i] == ... |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.