判断闰年

1、判断闰年

 1 #include<stdio.h>
 2 int main()
 3 {
 4     int year,leap;
 5     printf("please enter year: ");
 6     scanf("%d",&year);
 7     if(year%4==0)
 8     {
 9         if(year%100==0)
10         {if(year%400==0）
11         leap==1;
12         else
13             leap=0;
14         }
15         elae
16             leap=1;
17     }
18     else
19         leap=0;
20     if(leap)
21         printf("%d is ",year);
22     elae
23         printf("%d is not ",year);
24     printf("a leap year.
");
25     return 0;
26 }

法2：

 1 #include<stdio.h>
 2 int main()
 3 {
 4     int year,leap;
 5     printf("please enter year: ");
 6     scanf("%d",&year);
 7     if(year%4==0&&year%100!=0||(year%400==0))
 8         leap=1;
 9     else
10         leap=0;
11     if(leap)
12         printf("%d is ",year);
13     else
14         printf("%d is not ",year);
15     printf("a leap year.
");
16     return 0;
17 }

法3

 1 #include<stdio.h>
 2 int main()
 3 {
 4     int year,leap;
 5     printf("please enter year: ");
 6     scanf("%d",&year);
 7     if(year%4!=0)
 8         leap=0;
 9     else
10         if(year%100!=0)
11             leap=1;
12         else
13             if(year%400!=0)
14                 leap=0;
15             else
16                 leap=1;
17         
18     if(leap)
19         printf("%d is ",year);
20     else
21         printf("%d is not ",year);
22     printf("a leap year.
");
23     return 0;
24 }