openjudge 百练1664:Placing apples

题目：

Placing apples

View Submit Statistics Hint Clarify

总Time Limit: 1000ms Memory Limit: 65536kB

Description

We are going to place M same apples into N same plates.

There could be some empty plates.

How many methods do we have?

When we have 7 applesand 3 plates, the methods, (1, 5, 1) and (5, 1, 1) are the same.

Input

The first line is the number of test cases, t. 0<=t<=20

The next t lines are test cases containing two numbers, M and N. 1<=M, N<=10.

Output

Output the numbers of method in each test case in one line.

Sample Input

1

7 3

Sample Output

8

代码：

#include <iostream>
#include <cstring>
#include <cstdio>

using namespace std;
int ans;

int dfs(int m, int n){
    if(m== || n==) return ;
    if(m<n) return dfs(m, m);
    else if(m==n) return +dfs(m, m-);
    else return dfs(m, n-) + dfs(m-n, n);
}

int main(){
    int t, m, n;
    cin>>t;
    while(t--){
        cin>>m>>n;
        cout<<dfs(m, n)<<endl;
    }
    return ;
}
           

好的题解以及关于整数拆分的博客：

http://blog.csdn.net/pi9nc/article/details/8142091

http://blog.chinaunix.net/uid-26548237-id-3503956.html

http://www.cnblogs.com/xiaoxian1369/archive/2011/09/12/2174212.html

https://site.douban.com/191996/widget/notes/11374359/note/262068151/

http://www.cppblog.com/superKiki/archive/2010/05/27/116506.html