CF414BMashmokh and ACMDP

#include <cstdio>
#include <cstring>
#include <cmath>
#include <algorithm>
#include <climits>
#include <string>
#include <iostream>
#include <map>
#include <cstdlib>
#include <list>
#include <set>
#include <queue>
#include <stack>
using namespace std;
int n,k;
int dp[2222][2222];
const int mod= 1e9+7;
int dfs(int x,int pre)
{
    if(~dp[x][pre]) return dp[x][pre];
    if(x==k) return dp[x][pre]=1;
    int ret=0;
    for(int i= 1;i*pre<=n;i++)
        ret+=dfs(x+1,i*pre),ret%=mod;
    return dp[x][pre]=ret;
}
int main()
{
    scanf("%d%d",&n,&k);
    memset(dp,-1,sizeof(dp));
    cout<<dfs(0,1)<<endl;
    return 0;
}