背包问题

#include<list>
#include<iostream>
using namespace std;

list<int> list1;

void find_factor(int sum, int n)
{
// 递归出口
if (sum <= 0 || n <= 0)
return;

// 输出找到的结果
if (sum == n)
{
for (list<int>::iterator ite = list1.begin(); ite != list1.end(); ite++)
cout << *ite << " + ";
cout << n << endl;
}

//典型的01背包问题
list1.push_back(n);         //放n，n-1个数填满sum-n
find_factor(sum - n, n - 1);
list1.pop_back();         //不放n，n-1个数填满sum
find_factor(sum, n - 1);
}

int main()
{
int sum, n;
cout << "请输入你要等于多少的数值sum:" << endl;
cin >> sum;
cout << "请输入你要从1.....n数列中取值的n：" << endl;
cin >> n;
cout << "所有可能的序列，如下：" << endl;
find_factor(sum, n);

system("pause");
return 0;
}