HDU 5139

 1 #include <iostream>
 2 #include <cstdio>
 3 using namespace std;
 4 const int N=1000002;
 5 const int mod=1000000007;
 6 int n[N],f[N];
 7 void getnum(){
 8     n[0]=f[0]=1;
 9     for(int i=1;i<N;i++){
10         int tem=n[i-1];
11         f[i]=f[i-1];
12         for(int j=(i-1)*10+1;j<=i*10;j++){
13             tem=(long long) tem*j%mod;
14             f[i]=(long long) f[i]*tem%mod;
15         }
16         n[i]=tem;
17     }
18 }
19 int main()
20 {    getnum();
21     int a;
22     while(scanf("%d",&a)!=EOF){
23         if(a%10==0)printf("%d\n",f[a/10]);
24         else {
25             int i,k,j=a%10;
26             i=k=a/10;
27             int tem=n[i],sum=f[i];
28             for(i=i*10+1;i<=a;i++){
29                 tem=(long long) tem*i%mod;
30                 sum=(long long) sum*tem%mod;
31             }
32             printf("%d\n",sum);
33         }
34     }
35     return 0;
36 }