TINK|无重复字符的子串

#include <bits/stdc++.h>
using namespace std;
int q[100005];
string s;
set <char> vis;
signed main(){
	cin.tie(nullptr) -> sync_with_stdio(0);
	cout.tie(nullptr) -> sync_with_stdio(0);
	cin >> s;
	int cnt = 0, t = 0;
	for(int i = 0; i < s.length(); i++){
		while(vis.find(s[i]) != vis.end())vis.erase(s[t++]);
		vis.insert(s[i]);
		cnt += i - t + 1;
	}
	cout << cnt;
	return 0;
}