#include<stdio.h> int months[13] ={0,31,28,31,30,31,30,31,31,30,31,30,31}; bool IsRun(int year){ if(year%100!=0&&year%4==0) return true; if(year%400==0) return true; else return false; } void NextDay(int &year,int &month,int &day){ int maxday = mont...