C语言程序设计 计算日期答:if((year%400==0)||(year%4==0&&year%100!=0)) a[1]++;if(day>a[mouth-1]||day<1)return true;else return false;} void main(){ int i,year,mouth,day;int sum,sign;int a[12]={31,28,31,30,31,30,31,31,30,31,30,31};do { sum=0;sign=0;puts("请输入年、月、...