[local]1[/local]

#include<stdio.h>
int  main()
{
    int leap,year;
    printf("please enter a year\n");
    scanf("%d",year);
    if(year%4==0)
    {
        if(year%100==0)
        {
            if(year%400==0)
            {
                leap=1;
                else leap=0;
            }
            else
            leap=1;
        }
        else
        leap=0;
    }
    if(leap)
    {
    printf("闰");
    else
    printf("ping")
    }
    return 0;
}

基本上没改你的程序多少
#include<stdio.h>
 int  main()
 {
     int leap,year;
     printf("please enter a year\n");
     scanf("%d",&year);
     if(year%4==0)
     {
         if(year%100==0)
         {
             if(year%400==0)
             {
                 leap=1;
             }
             else
             leap=0;
         }
         else
         leap=1;
     }
     else
     leap=0;
     if(leap)
     printf("%d是闰年",year);
     else
     printf("%d不是闰年",year);
     getchar();
     return 0;
 }

#include<stdio.h>
int main(void)
{
    int year, leap;
    printf("输入判断年数:\n");
    scanf_s("%d",&year);
    if ((year % 4 == 0 && year % 100 != 0) || (year % 400 == 0))
    {
        leap = 1;
    }
    else
    {
        leap = 0;
    }
    if (leap == 1)
    {
        printf("\n%d此年是闰年\n", year);
    }
    else
    {
        printf("%d此年非闰年\n", year);
    }

    return 0;
}