int sumday(int month,int day){int daytab[13]={0,31,28,31,30,31,30,31,31,30,31,30,31};int i;for(i=0;i<month;i++)day+=daytab[i];return(day);}int leap(int year){int leap;leap=(year%4==0&&year%100!=0||year%400==0);return(leap);}