N!

Time Limit: 10000/5000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)
Total Submission(s): 34337    Accepted Submission(s): 9604

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

123

 

Sample Output

126

 

AC代码：

[cpp] view plaincopy

1. #include<iostream>  
2. using namespace std;  
3. int a[40000];  
4. int main()  
5. {  
6.     int N,i,j,pre;  
7.     while(cin>>N)  
8.     {  
9.         a[0]=1;  
10.         a[1]=1;  
11.         if(N==0||N==1){cout<<1<<endl;continue;}  
12.         for(i=2;i<=N;i++)  
13.         {  
14.             pre=0;  
15.             for(j=1;j<=a[0];j++)  
16.             {  
17.                 a[j]=a[j]*i;  
18.                 a[j]+=pre;//加上进位  
19.                 pre=a[j]/10;//进位值  
20.                 a[j]%=10;//本位  
21.             }  
22.             while(pre)  
23.             {  
24.                 a[j]=pre%10;  
25.                 a[0]=j;  
26.                 pre/=10;  
27.                 j++;  
28.             }  
29.         }  
30.         for(i=a[0];i>=1;i--)  
31.         {cout<<a[i];}  
32.         cout<<endl;  
33.     }  
34.     return 0;  
35. }