划分数

#include<cstdio>#define N 1001#define Mod (long long)(1e9+7)using namespace std;long long n,m;long long dp[N][N];int main(){    for(int i=1;i<=1000;i++)        dp[i][1]=1;    for(int i=1;i<=1000;++i)    {        for(int j=2;j<=1000;++j)          {            if(i==j)                dp[i][j]=1;            else if(i<j)                dp[i][j]=0;             else                dp[i][j]=(dp[i-1][j-1]+dp[i-j][j])%Mod;        }    }    while(scanf("%lld%lld",&n,&m))    {        if(n==0&&m==0)            break;        int sum=0;        for(int j=1;j<=m;j++)            sum=(sum+dp[n][j])%Mod;        printf("%lld\n",sum);    }    return 0;}