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1 class Solution { 2 public void sortColors(int[] nums) { 3 if(nums == null || nums.length == 0) return; 4 int count0 = 0; 5 int count1 = 0; 6 int count2 = 0... 阅读全文
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用Binary search 先搜索row 再搜索col 阅读全文
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可以用String.join 方法 String.join("/", stack);每个元素之间用"/"分开 阅读全文
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1 class Solution { 2 public String addBinary(String a, String b) { 3 if(a.length() == 0 && b.length() == 0) return null; 4 StringBuilder sb1 = new StringBuilder(a); 5 ... 阅读全文
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1 class Solution { 2 public int minPathSum(int[][] grid) { 3 if(grid == null) return 0; 4 int row = grid.length; 5 int col = grid[0].length; 6 int[][] res = ... 阅读全文
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1 class Solution { 2 public int uniquePathsWithObstacles(int[][] obstacleGrid) { 3 if(obstacleGrid == null) return 0; 4 int row = obstacleGrid.length; 5 int col = obs... 阅读全文
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1 class Solution { 2 public ListNode rotateRight(ListNode head, int k) { 3 if(head == null) return null; 4 int n = 0; 5 ListNode node1 = head; 6 ListNode las... 阅读全文
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1 class Solution { 2 public int[] plusOne(int[] digits) { 3 int n = digits.length; 4 int[] res = new int[n+1]; 5 int carry = 0; 6 for(int i = n - 1; i >= 0; ... 阅读全文
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https://leetcode.com/problems/permutation-sequence/discuss/22508/An-iterative-solution-for-reference 阅读全文
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跟spiral matrix类似 阅读全文