求N!

 

#include<stdio.h>#define N 1000    //要计算的Nlong s[N]={1,1},n=N,t=2,a=1,b=0;int main()//雨中飞燕之作{    for(;a<=*s||(++t<=n?(b=0,a=1):0);(*s==a++&&b)?(*s)++:0)        s[a]=(b+=s[a]*t)%10000,b/=10000;    for(printf("%d",s[*s]);--*s>0;)printf("%04d",s[*s]);    return 0;}

转载出处：http://www.programfan.com/blog/article.asp?id=25193