Files
2026-09-05 11:05:50 +08:00

44 lines
810 B
C++

#include <iostream>
using namespace std;
int primes[2001];
bool is_prime(int a) {
for (int i = 2; i * i <= a; i++) {
if (a % i != 0) {
continue;
} else {
return false;
}
}
return true;
}
void init_primes() {
int current_num = 2, i = 0;
for (;; current_num++) {
if (is_prime(current_num)) {
primes[i] = current_num;
i++;
}
}
}
int main() {
ios::sync_with_stdio(false);
cin.tie(nullptr);
int a;
cin >> a;
if (a % 2 != 0 || a < 6) {
cout << "Error!" << endl;
} else
for (int i = 0; primes[i] <= a / 2; i++) {
if (is_prime(a - primes[i])) {
cout << a << "=" << i << "+" << a - i << endl;
}
}
return 0;
}