#include <iostream>
using namespace std;
int main() {
int a = 10, b = 50;
________; // 此处填入代码
b -= a;
a += b;
cout << a << " " << b << endl;
return 0;
}
#include <iostream>
using namespace std;
int main() {
int cnt = 0;
for (char ch = '1'; ch <= '9'; ch++)
if (________) // 在此处填入代码
cnt++;
cout << cet << endl;
return 0;
}
#include <iostream>
using namespace std;
int main() {
int n = 17;
bool isprime = true;
for (int i = 2; i <= n; i++)
if (n % i == 0)
isprime = false;
cout << isprime << endl;
return 0;
}