new year and days

#include <stdio.h>
#include <string.h>
int main()
{
    char s1[30], s2[7];
    int i, j, n, l;
    gets(s1);
    l = strlen(s1);
    if(l<= 9)
    {
        n = (int)(s1[0]-'0');
        if(n==5 || n == 6)
        {
            printf("53");
            return 0;
        }
        else
        {
            printf("52");
            return 0;
        }
    }
    else
    {
        if(s1[1] != ' ')
        {
            s2[0] = s1[0];
            s2[1] = s1[1];
            n = atoi(s2);
            if(n <= 29)
            {
                printf("12");
                return 0;
            }
            else if(n == 30)
            {
                printf("11");
                return 0;
            }
            else
            {
                printf("7");
                return 0;
            }
        }
        else{
            printf("12");
            return 0;
        }
    }
    return 0;
}