2015年百度之星资格赛 A dp

#include <cstdio>#include <iostream>using namespace std;const int maxn = 1000000;#define INF 1000000007Llong long int dp[maxn+10];void fun(){    dp[0] = 1;    dp[1] = 1;    for(long long i = 2; i <= maxn;i++){        dp[i] = (dp[i-1] + ((long long)(i-1)) % INF * dp[i-2]) % INF;    }}int main(){    int t;    fun();    scanf("%d",&t);    int q = 1;        while(t--){        int a;                scanf("%d",&a);        printf("Case #%d:\n",q++);        printf("%I64d\n",dp[a]);    }     return 0;}