从键盘上任意输入一个年号，判断它是否是闰年。

#include <stdio.h>int main(){    int year,flag;    printf("Enter year:");    scanf("%d",&year);    if(year%4==0 &year%100!=0)        flag=1;    else        flag=0;    if(flag==1)        printf("%d is a leap year!\n",year);    else        printf("%d is not a leap year!\n",year);    return 0;}运行结果：