Description

Submission

class Solution {
public:
    int minDeletionSize(vector<string>& strs) {
        int n = strs.size();
        int l = strs[0].length();
        
        vector<int> cmp(n, 0);
        
        int ret = 0;
        for(int i = 0; i < l; ++i) {
            vector<int> newCmp(n, 0);
            bool merge = true;
            for(int j = 1; j < n; ++j) {
                if(cmp[j]) continue;
                if(strs[j-1][i] > strs[j][i]) {
                    ret++;
                    merge = false;
                    break;
                }
                if(strs[j-1][i] < strs[j][i]) {
                    newCmp[j] = 1;
                }
            }
            if(merge) {
                for(int i = 0; i < n; ++i) {
                    if(newCmp[i]) cmp[i] = 1;
                } 
            }
        }
        return ret;
    }
};