Problem:
Score : 200 points

Problem Statement

Given are two strings S and T.

Let us change some of the characters in S so that T will be a substring of S.

At least how many characters do we need to change?

Here, a substring is a consecutive subsequence. For example, xxx is a substring of yxxxy, but not a substring of xxyxx.

Constraints

The lengths of S and T are each at least 1 and at most 1000.

The length of T is at most that of S.

S and T consist of lowercase English letters.

Input

Input is given from Standard Input in the following format:

S
T

Output

Print the minimum number of characters in S that need to be changed.

Sample Input 1

cabacc
abc

Sample Output 1

1

For example, changing the fourth character a in S to c will match the second through fourth characters in S to T.

Since S itself does not have T as its substring, this number of changes - one - is the minimum needed.

Sample Input 2

codeforces
atcoder

Sample Output 2

6

Solution in C++ (GCC 9.2.1) (judge verdict: Runtime Error)

#include<bits/stdc++.h>
using namespace std;
using ll=long long;
string s, t;
int check(int tpos,int spos) {
	int ans = 0;
	int tl = tpos + 1;
	int sl = spos + 1;
	while (tpos >= 0) {
		if (s[spos] != t[tpos])ans++;
		tpos--;
		spos--;
	}
	while (tl < t.size()) {
		if (t[tl] != s[sl])ans++;
		tl++; sl++;
	}
	return ans;
}
int main() {
	cin >> s >> t; vector<int>res;
	set<char>st; map<char, int>mp;
	for (int i = 0; i < t.size(); ++i) {
		mp[t[i]] = i;
	}
	for (char c : t)st.insert(c);
	for (int i = 0; i < s.size(); ++i) {
		if (st.find(s[i]) != st.end()) {
			if (i >= mp[s[i]] && (s.size() - 1) - i >= ((t.size() - 1) - mp[s[i]])) {
				int temp = check(mp[s[i]], i);
				res.push_back(temp);
			}
			//else cout << i << "\n";
		}
	}
	sort(res.begin(), res.end());
	cout << res[0];
	return 0;
}