GESP三级 - 无暇素数算法题解

#include #include #include #include

using namespace std;

bool isPrime(int num) { if (num < 2) { return false; } for (int i = 2; i <= sqrt(num); i++) { if (num % i == 0) { return false; } } return true; }

vector getPermutations(int num) { vector permutations; string numStr = to_string(num); sort(numStr.begin(), numStr.end()); do { int permutation = stoi(numStr); permutations.push_back(permutation); } while (next_permutation(numStr.begin(), numStr.end())); return permutations; }

int main() { string input; cin >> input;

vector<int> primes;
for (int i = 0; i < input.size() - 1; i++) {
    for (int j = i + 1; j < input.size() - 1; j++) {
        int num = stoi(input.substr(i, 1) + input.substr(j, 1));
        if (isPrime(num)) {
            primes.push_back(num);
        }
    }
}

sort(primes.begin(), primes.end());
primes.erase(unique(primes.begin(), primes.end()), primes.end());

for (int i = 0; i < primes.size(); i++) {
    if (i == primes.size() - 1) {
        cout << primes[i];
    } else {
        cout << primes[i] << ',';
    }
}

return 0;

}