LeetCode 581. 最短无序连续子数组

class Solution {
public:
    int findUnsortedSubarray(vector<int>& nums) {
        int n=nums.size();
        int l=0,r=n-1;
        while(l<n-1&&nums[l]<=nums[l+1]) l++;
        while(r>0&&nums[r]>=nums[r-1])  r--;
        int min_num=INT_MAX,max_num=INT_MIN;
        if(l==n-1||r==0)    return 0;
        for(int i=0;i<r;i++)    max_num=max(max_num,nums[i]);
        for(int i=l;i<n;i++)    min_num=min(min_num,nums[i]);
        while(l>=0&&nums[l]>min_num)    l--;
        while(r<n&&nums[r]<max_num) r++;
        return r-l-1;
    }
};