#include<stdio.h>
int main()
{
    int month;
    int days[12]={31,28,31,30,31,30,31,31,30,31,30,31}
    scanf("%d",&month);
    if(month<1||month>12)
    {
        printf("Invalid input");
    }
    else{
        if(month==2)
        {
            printf("28 days (29 in leap years)");
        }
        else
        printf("%d days",days[month-1]);
    }
    return 0;
    
}