#include <stdio.h> int Is_run(int year){ return (year % 4 == 0 && year % 100 != 0)||year % 400 == 0; } void Date(int year,int month,int day,int after_day){ int date[2][13]={{0,31,28,31,30,31,30,31,31,30,31,30,31},{0,31,29,31,30,31,30,31,31,30,31,30,31}}; int next_year,nex...