【数组】递增的三元子序列

题目：

 

 

解答：

 

 

class Solution {
public:
    bool increasingTriplet(vector<int>& nums) 
    {
        int len = nums.size();
        
        if (len < 3) 
        {
            return false;
        }
        
        int small = INT_MAX;
        int mid = INT_MAX;
        
        for (auto num : nums) 
        {
          if (num <= small) 
          {
            small = num;
          } else if (num <= mid) 
          {
            mid = num;
          } 
          else if (num > mid) 
          {
            return true;
          }
        }
        return false;    

    }
};