方法一`
#include<stdio.h> int main() { int n; scanf("%d",&n); if(n%4==0) { if(n%100!=0) printf("%d is a leap year\n",n); else if(n%400==0) printf("%d is a leap year\n",n); } else printf("%d is not a leap year\n",n); return 0; }方法二
#include<stdio.h> int main() { int n; scanf("%d",&n); if((n%4==0)&&(n%100!=0)||n%400==0) printf("%d is a leap year\n",n); else printf("%d is not a leap year\n",n); return 0; }自动输出1900~2100年间的闰年
#include<stdio.h> int main() { int n; for(n=1900;n<=2100;n++) { if((n%4==0)&&(n%100!=0)||n%400==0) printf("%d is a leap year\n",n); } return 0; }