最简单的题解

#include <iostream>
using namespace std;
int main() {
    int month, day;
    cin >> month >> day;
    switch (month) {
        case 1: case 3: case 5: case 7: case 8: case 10: case 12:
            switch (day % 2) {
                case 0:
                    cout << "Oh!No!" << endl;
                    break;
                case 1:
                    cout << "Play!" << endl;
                    break;
            }
            break;
        case 4: case 6: case 9: case 11:
            switch (day % 2) {
                case 0:
                    cout << "Play!" << endl;
                    break;
                case 1:
                    cout << "Oh!No!" << endl;
                    break;
            }
            break;
        case 2:
            switch (day % 2) {
                case 0:
                    cout << "Play!" << endl;
                    break;
                case 1:
                    cout << "Oh!No!" << endl;
                    break;
            }
            break;
    }
    return 0;
}