HDU 1042 N!

Problem Description

Given an integer N(0 ≤ N ≤ 10000), your task is to calculate N!

Input

One N in one line, process to the end of file.

Output

For each N, output N! in one line.

Sample Input

1
2
3

Sample Output

1
2
6

题目大意：

大数阶乘，0<=n<=10000;求n的阶乘。

c++

#include <iostream>#include<cstring>using namespace std;int a[1600100];int main(){    int b,c,d,e,f,g;    while(cin>>b)    {        memset(a,0,sizeof(a));        a[0]=1;g=0;     //a数组中每一位用来存放一位数，g用来记录位数        for(c=1;c<=b;c++)        {            for(d=0;d<=g;d++)    //a数组中每一位都与c相乘            {                a[d]=a[d]*c;            }            for(d=0;d<=g;d++)            {                if(a[d]>=10)    //a数组中数值>=10时进位                {                    a[d+1]=a[d]/10+a[d+1];                    a[d]=a[d]%10;                }            }            if(a[g+1]!=0)  //判断g的下一位是否为0                g++;            while(a[g]>=10)  //使a数组中每一位只存放一位数            {                a[g+1]=a[g]/10;a[g]=a[g]%10;g++;            }        }        for(c=g;c>=0;c--)        {            cout<<a[c];        }        cout<<endl;    }    return 0;}