944. Delete Columns to Make Sorted

class Solution {
public:
    int minDeletionSize(vector<string>& strs) {
        int m = strs.size(), n = strs[0].size();
        int cnt = 0;
        for (int j = 0; j < n; j++) {
            for (int i = 0; i < m - 1; i++) {
                if (strs[i][j] > strs[i + 1][j]) {
                    cnt++; break;
                }
            }
        }
        return cnt;
    }
};