func_code_string: #include <bits/stdc++.h>   #pragma comment(linker,  /STACK:256000000 )   using namespace std;   int n, k;   int a[200000];   bool ok() {     int cur = a[k - 1];     for (int i = k; i < n; ++i) {       if (a[i] != cur) return false;     }     return true;   }   int main() {     ios_base::sync_with_stdio(false);     cin >> n >> k;     for (int i = 0; i < (int)(n); i++) cin >> a[i];     if (!ok())       cout << -1 << endl;     else {       int ans = 0;       int cur = a[k - 1];       for (int i = 0; i < (int)(k); i++) {         if (a[i] != cur) ans = i + 1;       }       cout << ans << endl;     }     return 0;   }   