Karmen199x的博客

63. Unique Paths IIDescription描述：https://leetcode.com/problems/unique-paths-ii/description/题意：m列 × n行 的有障碍物的网格，从左上角第一个到右下角最后一个（只能往右和下这两个方向走），有多少条不重复的路径Solution: (Java)class Solution { public ...

62. Unique PathsDescription描述：https://leetcode.com/problems/unique-paths/description/题意：m列 × n行 的网格，从左上角第一个到右下角最后一个（只能往右和下这两个方向走），有多少条不重复的路径Solution 1: (Java) 超时class Solution { public int pa...

61. Rotate ListDescription描述：https://leetcode.com/problems/rotate-list/description/题意：对于给定链表，向右旋转k个位置。Solution: (Java)/** * Definition for singly-linked list. * public class ListNode { * i...

60. Permutation SequenceDescription描述：https://leetcode.com/problems/permutation-sequence/description/题意：给定1~n这n个数，返回第k个排列。Solution: (Java)class Solution { public String getPermutation(int n, ...

59. Spiral Matrix IIDescription描述：https://leetcode.com/problems/spiral-matrix-ii/description/题意：给定整数n，按螺旋顺序填充n×n（从1~n^2）的二维矩阵。Solution: (Java)class Solution { public int[][] generateMatrix(in...

58. Length of Last WordDescription描述：https://leetcode.com/problems/length-of-last-word/description/题意：返回字符串中最后一个单词的长度Solution: (Java)class Solution { public int lengthOfLastWord(String s) { ...

56. Merge IntervalsDescription描述：https://leetcode.com/problems/merge-intervals/description/题意：给定一组区间，合并重叠的区间。Solution: (Java)class Solution { private class IntervalComparator implements Compa...

45. Jump Game IIDescription描述：https://leetcode.com/problems/jump-game-ii/description/题意：给定一维数组，数组中的值表示该位置能往后跳的最大位置，求达到最后一个位置需要跳的最小步数。Solution: (Java)class Solution { public int jump(int[] num...

55. Jump GameDescription描述：https://leetcode.com/problems/jump-game/description/题意：给定一维数组，数组中的值表示该位置能往后跳的最大位置，求是否能到达数组的最后一个位置。Solution: (Java)class Solution { public boolean canJump(int[] nums...

54. Spiral MatrixDescription描述：https://leetcode.com/problems/spiral-matrix/description/题意：将一个数据按照螺旋状进行遍历。Solution: (Java)class Solution { public List<Integer> spiralOrder(int[][] matrix...

53. Maximum SubarrayDescription描述：https://leetcode.com/problems/maximum-subarray/description/题意：找出数组中和最大的子数组。Solution 1: (Java)class Solution { public int maxSubArray(int[] nums) { in...

50. Pow(x, n)Description描述：https://leetcode.com/problems/powx-n/description/题意：求 x 的 n 次方。Solution: (Java)class Solution { public double myPow(double x, int n) { if (n == 0) ...

49. Group AnagramsDescription描述：https://leetcode.com/problems/group-anagrams/description/题意：将字符串按照组成的字母相同进行分类。Solution: (Java)class Solution { public List<List<String>> groupAnagr...

48. Rotate ImageDescription描述：https://leetcode.com/problems/rotate-image/description/题意：将一个矩阵（二维数组）顺时针旋转90度，不能分配额外的二维空间。Solution: (Java)class Solution { public void rotate(int[][] matrix) { ...

47. Permutations IIDescription描述：https://leetcode.com/problems/permutations-ii/description/题意：返回一个数组（数组中可能有重复）中所有的唯一的全排列。Solution: (Java)class Solution { List<List<Integer>> resul...

46. PermutationsDescription描述：https://leetcode.com/problems/permutations/description/题意：返回一个数组的全排列Solution: (Java)class Solution { List<List<Integer>> result = new ArrayList<&g...

43. Multiply StringsDescription描述：https://leetcode.com/problems/multiply-strings/description/题意：将字符串表示的两个数相乘计算结果，不可调用大整数包或直接转为整数相乘。Solution 1: (Java)class Solution { public String multiply(St...

40. Combination Sum IIDescription描述：https://leetcode.com/problems/combination-sum-ii/description/题意：从给定数组中找出所有可能的组合（一个数只能取一次，数组中有重复的数），使得组合的和等于目标值。Solution: (Java)class Solution { List<Lis...

39. Combination SumDescription描述：https://leetcode.com/problems/combination-sum/description/题意：从给定数组中找出所有可能的组合（一个数可以取多次），使得组合的和等于目标值。Solution: (Java)class Solution { List<List<Integer&gt...

37. Sudoku SolverDescription描述：https://leetcode.com/problems/sudoku-solver/description/题意：求解数独（9×9）Solution 1: (Java)class Solution { ArrayList<ArrayList<Character>> row = new Arr...

38. Count and SayDescription描述：https://leetcode.com/problems/count-and-say/description/题意：从1开始，从左至右，对数字计数，将个数和对应的数字连接（计数并读出）并作为下一个数。Solution: (Java)class Solution { public String countAndSay(...

35. Search Insert PositionDescription描述：https://leetcode.com/problems/search-insert-position/description/题意：在有序数组中查找目标，不存在则返回插入的下标。Solution: (Java)class Solution { public int searchInsert(int...

36. Valid SudokuDescription描述：https://leetcode.com/problems/valid-sudoku/description/题意：检查数独（未解答之前）是否有效Solution: (Java)class Solution { public boolean isValidSudoku(char[][] board) { ...

34. Find First and Last Position of Element in Sorted ArrayDescription描述：https://leetcode.com/problems/find-first-and-last-position-of-element-in-sorted-array/description/题意：在有序数组中，查找目标数的第一次和最后一次出现...

33. Search in Rotated Sorted ArrayDescription描述：https://leetcode.com/problems/search-in-rotated-sorted-array/description/题意：在旋转有序数组中，查找指定的数，时间复杂度要求O(log n)。Solution: (Java)class Solution { pu...

31. Next PermutationDescriptionImplement next permutation, which rearranges numbers into the lexicographically next greater permutation of numbers.If such arrangement is not possible, it must rear...

29. Divide Two IntegersDescription描述：https://leetcode.com/problems/divide-two-integers/description/Solution: (Java)class Solution { public int divide(int dividend, int divisor) { if (d...

11. Container With Most WaterDescriptionGiven n non-negative integers a1, a2, ..., an , where each represents a point at coordinate (i, ai). n vertical lines are drawn such that the two endpoints o...

14. Longest Common PrefixDescriptionWrite a function to find the longest common prefix string amongst an array of strings.If there is no common prefix, return an empty string "".Example 1:Input...

13. Roman to IntegerDescriptionRoman numerals are represented by seven different symbols: I, V, X, L, C, D and M.Symbol ValueI 1V 5X 10L 5...

9.Palindrome NumberDescriptionDetermine whether an integer is a palindrome. An integer is a palindrome when it reads the same backward as forward.Example 1:Input: 121Output: trueExample 2:Inp...

12. Integer to RomanDescriptionRoman numerals are represented by seven different symbols: I, V, X, L, C, D and M.Symbol ValueI 1V 5X 10L 5...

DescriptionImplement atoi which converts a string to an integer.The function first discards as many whitespace characters as necessary until the first non-whitespace character is found.Then, start...

7.Reverse IntegerDescriptionGiven a 32-bit signed integer, reverse digits of an integer.ExampleExample 1:Input: 123Output: 321Example 2:Input: -123Output: -321Example 3:Input: 120Output:...

6.ZigZag ConversionDescriptionThe string “PAYPALISHIRING” 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 legibil...

5.Longest Palindromic SubstringDescriptionGiven a string s, find the longest palindromic substring in s. You may assume that the maximum length of s is 1000.ExampleInput: "babad"Output: "bab"Not...

3.Longest Substring Without Repeating CharactersDescription:Given a string, find the length of the longest substring without repeating characters.Example:Input: "abcabcbb"Output: 3 Explanation: ...

1.Two SumDescription:Given an array of integers, return indices of the two numbers such that they add up to a specific target.You may assume that each input would have exactly one solution, and you...

15. 3SumDescriptionGiven an array nums of n integers, are there elements a, b, c in nums such that a + b + c = 0? Find all unique triplets in the array which gives the sum of zero.Note:The solut...

18. 4SumDescriptionGiven an array nums of n integers and an integer target, are there elements a, b, c, and d in nums such that a + b + c + d = target? Find all unique quadruplets in the array whic...