#include<stdio.h>
int main () {
    int month;
    scanf("%d",&month);
    switch(month) {
        case 1;case 3;case 5;case 7;case 8;case 10;case 12;
        printf("31 days\N");
        break;
        case 4;case 6;case 9; case 11;
        printf("30 days\N");
        break;
        case 2;
            printf("28 or 29 days\N");
            break;
            default;
            printf("Invalid input\N");
    }
    return 0;
}