大整数存储及运算——求100的阶乘

来源：互联网发布：tl wr886n主人网络编辑：程序博客网时间：2024/06/05 06:42

用C语言实现：

#include"stdio.h"
void main()
{
   long a[256], b, d;
   int m = 1, n, i, j, r;
   scanf("%d", &n);
   a[1] = 1;
   d = 0;
   for (i = 2; i <= n; i = i + 1){
       for (j = 1; j <= m; j = j + 1){
           b = a[j] * i +d;               //存储中间结果
           a[j] = b % 1000000;
           d = b / 1000000;
       }
       if (d != 0){                      //进位处理
       a[j] = d % 1000000;
       d = d / 1000000;
       m = m + 1;
       }
   }
   printf("%d ", a[m]);
   for (i = m-1; i >= 1; i--){
       if(a[i] > 99999){
           printf("%d ", a[i]);
           continue;
       }
       if(a[i] > 9999){
           printf("0","%d ", a[i]);
           continue;
       }
       if(a[i] > 999){
           printf("00","%d ", a[i]);
           continue;
       }
       if(a[i] > 99){
           printf("000","%d ", a[i]);
           continue;
       }
       if(a[i] > 9){
           printf("0000","%d ", a[i]);
           continue;
       }
       printf("00000","%d ",a[i]);
   }
   printf("\n");
}

运行结果：

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