#include <stdio.h> short leapyear(int year)//判断是否为闰年。f=1是闰年。f=0,不是闰年 { short f = 0; if (year % 400 == 0) f = 1; if (year % 4 == 0 && year % 100 != 0) f = 1; return f; } int month_days(int year, int month)//返回year,month的天数 { int d[13] = { 0,31,28,31,30,31,30,31,31,30,31,30,31 }; if (lea...