fork download
copy 
  1. #include <bits/stdc++.h>
  2. using namespace std;
  3. void test_case() {
  4.   int n;
  5.   cin >> n;
  6.   string s;
  7.   cin >> s;
  8.   set<char> ss;
  9.   for (int i = 0; i < n; ++i) {
  10.     ss.insert(s[i]);
  11.   }
  12.   int unique = (int)ss.size();
  13.   vector<bool> vis(26, false);
  14.   vector<int> num_unique(n+1);
  15.   num_unique[0] = 0;
  16.   for (int i = 0; i < n; ++i) {
  17.     if (!vis[s[i]]) {
  18.       num_unique[i+1] = num_unique[i] + 1;
  19.       vis[s[i]] = true;
  20.     }
  21.     else {
  22.       num_unique[i+1] = num_unique[i];
  23.     }
  24.   }
  25.   int i = 1, j = n, maxi = 0, ans = 0;
  26.   while (i <= j) {
  27.     int dist = num_unique[j]-num_unique[i];
  28.     if (dist >= maxi) {
  29.       maxi = dist;
  30.       ans = j-i+1;
  31.     }
  32.     if (i+1 < n+1 && num_unique[i+1] == num_unique[i]) {
  33.       ++i;
  34.     }
  35.     else if (j-1 > i && num_unique[j-1] == num_unique[j]) {
  36.       --j;
  37.     }
  38.     else {
  39.       ++i;
  40.     }
  41.   }
  42.   cout << ans << '\n';
  43. }
  44. int main(int argc, char const *argv[]) {
  45.   ios_base::sync_with_stdio(false), cin.tie(nullptr);
  46.   int tc = 1;
  47.   // cin >> tc;
  48.   while (tc--) {
  49.     test_case();
  50.   }
  51.   return 0;
  52. }
  53.  
Success #stdin #stdout 0.01s 5464KB
comments (?)
stdin
copy 
Standard input is empty
stdout
copy 
0
https://ideone.com/8H7sXX
language:
C++14 (clang 8.0)
created:
2 years ago
visibility:
secret

Share or Embed source code

Discover > Sphere Engine API

The brand new service which powers Ideone!

Discover > IDE Widget

Widget for compiling and running the source code in a web browser!