练习3-5 输出闰年（15 分）water

#include<stdio.h>

int main()
{
    int N,i,cnt;

    scanf("%d",&N);

    if(N<=2000||N>2100) printf("Invalid year!");

    for(i=2001;i<=N;i++){
        if(((i%4==0)&&(i%100!=0))||(i%400==0)){
            printf("%d\n",i);
            cnt++;
        }
    }

    if(cnt==0) printf("None");

    return 0;
 }