Code Forces 414B 很不错的双手，以促进合规

http://codeforces.com/problemset/problem/414/B

题目挺不错的。留个纪念，活动脑筋不错的题目

#include<iostream>
#include<cstdio>
#include<list>
#include<algorithm>
#include<cstring>
#include<string>
#include<queue>
#include<stack>
#include<map>
#include<vector>
#include<cmath>
#include<memory.h>
#include<set>

#define ll long long

#define eps 1e-8

#define inf 0xfffffff

const ll INF = 1ll<<61;

using namespace std;

//vector<pair<int,int> > G;
//typedef pair<int,int > P;
//vector<pair<int,int> > ::iterator iter;
//
//map<ll,int >mp;
//map<ll,int >::iterator p;

#define  MOD 1000000007

vector<int> G[2555];

int dp[2555][2555];

void init() {
	for(int i=1;i<=2000;i++)
		for(int j=1;j<=i;j++)
			if(i%j == 0)
				G[i].push_back(j);
}

int main() {
	init();
	int n,k;
	scanf("%d %d",&n,&k);
	for(int i=1;i<=n;i++)
		dp[1][i] = 1;
	for(int i=2;i<=k;i++) {
		for(int j=1;j<=n;j++) {
			for(int kk=0;kk<G[j].size();kk++) {
				int tmp = G[j][kk];
				dp[i][j] += dp[i-1][tmp];
				dp[i][j] %= MOD;
			}
		}
	}
	int ans = 0;
	for(int i=1;i<=n;i++)
		ans = (ans + dp[k][i])%MOD;
	printf("%d\n",ans);
}