func_code_string: #include <bits/stdc++.h>   using namespace std;   int32_t main() {     ios::sync_with_stdio(false);     cin.tie(nullptr);     cout.tie(nullptr);     long long n;     cin >> n;     string s;     cin >> s;     set<char> all;     for (auto c : s) all.insert(c);     const long long sz = all.size();     if (sz == 1) {       cout <<  1 n ;       return 0;     }     long long lo = 1;     long long hi = n;     long long a = n;     while (lo <= hi) {       long long mid = (lo + hi) / 2;       map<char, long long> freq;       bool poss = false;       long long dist = 0;       for (long long i = 0; i < mid; i++) {         freq[s[i]]++;         if (freq[s[i]] == 1) dist++;       }       for (long long i = mid; i < n; i++) {         if (dist == sz) poss = true;         if (--freq[s[i - mid]] == 0) dist--;         if (++freq[s[i]] == 1) dist++;         if (dist == sz) poss = true;       }       if (poss) {         a = min(a, mid);         hi = mid - 1;       } else         lo = mid + 1;     }     cout << a <<   n ;     return 0;   }   