50分求调

#include<bits/stdc++.h>
using namespace std;

int f(int n) {
	bool flag = 1;
	for (int i = 2; i <= sqrt(n); i++) {
		if (n % i == 0) {
			flag = 0;
			break;
		}
	}
	return flag;
}

int main() {
	int n;
	cin >> n;
	for (int i = 2; i <= n / 2; i++) {
		if (f(i) == 1 && f(n - i) == 1) {
			cout << n << "=" << i << "+" << n - i << "\n";
		}
	}
	return 0;
}