#include <bits/stdc++.h>
using namespace std;
int main() {
int year, month;
    cin >> year >> month;
    if (month == 1 || month == 3 || month == 5 || month == 7 || month == 8 || month == 10 || month == 12) {
        cout << 31;
    } else if (month == 4 || month == 6 || month == 9 || month == 11) {
        cout << 30;
    } else {
        if ((year % 4 == 0 && year % 100 != 0) || (year % 400 == 0)) {
            cout << 29;
        } else {
            cout << 28;
        }
    }
    return 0;
}
    

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

int main() { int a, b[13] = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}, c; cin >> a >> c; if ((a % 4 == 0 && a % 100 != 0) || (a % 400 == 0) ) {

	b[1] = 29;
}
cout << b[c - 1];
return 0;

}

#include using namespace std;

int main() { int y, m; cin >> y >> m; int day; // 大月 if(m == 1 || m == 3 || m == 5 || m == 7 || m == 8 || m == 10 || m == 12) day = 31; // 小月 else if(m == 4 || m == 6 || m == 9 || m == 11) day = 30; // 2月，判断闰年 else { //闰年：能被4整除但不能被100整除 或 能被400整除 if((y % 4 == 0 && y % 100 != 0) || (y % 400 == 0)) day = 29; else day = 28; } cout << day << endl; return 0; }