#include int month2day(int year,int month){ int tmp[12] = {31,28,31,30,31,30,31,31,30,31,30,31}; if (year % 4 == 0)tmp[1]++; return tmp[month-1]; } int main(){ int year,month,day; printf("Input year, month, day: \n"); scanf("%d %d %d",&year,&month,&day); for(;month>1;month--){ day += month2day(year,month); } printf("Days of year: %d",day); return 0; }