455.分发饼干

leetcode题目链接：https://leetcode.cn/problems/assign-cookies

leetcode AC记录：

代码如下：

public int findContentChildren(int[] g, int[] s) {Arrays.sort(g);Arrays.sort(s);int res = 0;int sIndex = 0;int gIndex = 0;while(gIndex < g.length && sIndex < s.length) {if(g[gIndex] <= s[sIndex]) {res++;gIndex++;} sIndex++;}return res;}

 376. 摆动序列

leetcode题目链接：https://leetcode.cn/problems/wiggle-subsequence

leetcode AC记录：

代码如下：

  //本体可以理解为升降的次数public int wiggleMaxLength(int[] nums) {int res = 1;int max = Integer.MIN_VALUE;int min = Integer.MAX_VALUE;int upOrDown = 2; // 0 降 1 升for(int i = 1;i <= nums.length -1;i++) {//下降if(nums[i-1] > nums[i]) {//初始值或者之前是上升，子序列长度增加if(upOrDown == 2 || upOrDown == 1) {res++;upOrDown = 0;}//上升} else if(nums[i-1] < nums[i]) {if(upOrDown == 2 || upOrDown == 0) {res++;upOrDown = 1;}}}return res;}

 53. 最大子序和

leetcode题目链接：https://leetcode.cn/problems/maximum-subarray

leetcode AC记录：

 代码如下：

 public int maxSubArray(int[] nums) {int currentSum = nums[0];int res = currentSum;for(int i = 1;i < nums.length;i++) {currentSum = nums[i] > currentSum + nums[i] ? nums[i] : currentSum + nums[i];res = res > currentSum ? res : currentSum;}return res;}

122.买卖股票的最佳时机II

leetcode题目链接：https://leetcode.cn/problems/best-time-to-buy-and-sell-stock-ii/

leetcode AC记录：

代码如下：

  public int maxProfit(int[] prices) {int res = 0;for(int i = 1;i <= prices.length - 1;i++) {if(prices[i-1] < prices[i]) {res += prices[i] - prices[i-1];}}return res;}

55. 跳跃游戏

leetcode题目链接：https://leetcode.cn/problems/jump-game

leetcode AC记录：

代码如下：

public boolean canJump(int[] nums) {int index = 0;int length = nums.length;while(index < nums.length) {if(index >= nums.length -1) {return true;} else if(nums[index] == 0) {return false;}int maxIndex = Integer.MIN_VALUE;for(int i = 1; i <= nums[index]; i++) {if(nums[index + i] + i + index >= nums.length -1) {return true;}if(maxIndex < 0 || nums[index + i] + i + index > maxIndex + nums[maxIndex]) {maxIndex = index + i;} }index = maxIndex;}return true;}

45.跳跃游戏II

leetcode题目链接：https://leetcode.cn/problems/jump-game-ii

leetcode AC记录：

代码如下：

public int jump(int[] nums) {int index = 0;int length = nums.length;int res = 0;while(index < nums.length -1) {int num = nums[index];int maxIndex = index;for(int i = 1;i <= num;i++) {if(index + i >= nums.length - 1) {return res + 1;} else if(nums[index + i] + index + i > nums[maxIndex] + maxIndex) {maxIndex = index + i;}}index = maxIndex;res++;// if(nums[maxIndex] + maxIndex >= nums.length -1) {//     return res+1;// }}return res;}