func_code_string: #include <bits/stdc++.h>   using namespace std;   bool isPrime(int n) {     if (n <= 1) return false;     for (int i = 2; i < n; i++)       if (n % i == 0) return false;     return true;   }   int main() {     int t;     cin >> t;     while (t--) {       int n;       cin >> n;       int sum = 0;       vector<long long> a(n + 1, 0);       long long odd = -1;       for (int i = 1; i <= n; i++) {         cin >> a[i];         sum += a[i];         if (a[i] & 1) odd = i;       }       if (isPrime(sum)) {         cout << n - 1 << endl;         for (int i = 1; i <= n; i++) {           if (i == odd) continue;           cout << i <<    ;         }         cout << endl;       } else {         cout << n << endl;         for (int i = 1; i <= n; i++) {           cout << i <<    ;         }         cout << endl;       }     }     return 0;   }   