[leetcode] 955. Delete Columns to Make Sorted II : https://leetcode.com/problems/delete-columns-to-make-sorted-ii/

Delete Columns to Make Sorted II.cc

class Solution {
public:
    int minDeletionSize(vector<string>& A) {
        int n = A.size();
        int m = A[0].size();
        int ans = 0;
        
        vector<bool> ordered(m, false);
        for(int j=0;j<m;j++){
            bool deletedRow = false;
            for(int i=1;i<n;i++){
                if(ordered[i] || A[i-1][j] <= A[i][j]) continue;
                ans++;
                deletedRow = true;
                break;
            }
            if(deletedRow) continue;
            for(int i=1;i<n;i++){
                ordered[i] = ordered[i] || (A[i-1][j] < A[i][j]);
            }
        }
        return ans;
    }
};