题解

#include <iostream>
using namespace std;
int main() {
    int a, b, c;
    cin >> a >> b >> c;
    if (c == 1) {
        int area = a * b;
        cout << area << endl;
    } else if (c == 2) {
        int perimeter = 2 * (a + b);
        cout << perimeter << endl;
    }
    return 0;
}