https://leetcode-cn.com/problems/increasing-triplet-subsequence/submissions/

    • 跟300题差不多
      1. public boolean increasingTriplet(int[] nums) {
      2.       if (nums == null || nums.length < 3) {
      3.           return false;
      4.       }
      5.       int[] ends = new int[3];
      6.       ends[0] = nums[0];
      7.       int right = 0; // 0..right有效区
      8.       int l = 0;
      9.       int r = 0;
      10.       int m = 0;
      11.       for (int i = 1; i < nums.length; i++) {
      12.           l = 0;
      13.           r = right;
      14.           while (l <= r) {
      15.               m = (l + r) >> 1;
      16.               if (nums[i] > ends[m]) {
      17.                   l = m + 1;
      18.               } else {
      19.                   r = m - 1;
      20.               }
      21.           }
      22.           right = Math.max(right, l);
      23.           if (right > 1) {
      24.               return true;
      25.           }
      26.           ends[l] = nums[i];
      27.       }
      28.       return false;
      29.   }