c语言每日练习，day day up！

#include<stdio.h> int main() { int day, month, year, num; printf("输入年月日\n"); scanf_s("%d%d%d", &year, &month, &day); switch (month) { case(1):num = day; break; case(2):num = day + 31; break; case(3):num = day + 59; break; case(4):num = day + 90; break; case(5):num = day + 120; break; case(6):num = day + 151; break; case(7):num = day + 181; break; case(8):num = day + 212; break; case(9):num = day + 243; break; case(10):num = day + 273; break; case(11):num = day + 304; break; case(12):num = day + 334; break; } if (year / 4 == 0 && month > 2) { num += 1; printf("这是一年的第%d天", num); } else { printf("这是这一年的第%d天", num); } return 0; }