C++组合问题

/*5个中选3个数*/
#include <bits/stdc++.h>
using namespace std;
int num[5] = {1,2,3,4,5};
int processed[3];
void combination(int start,int picked)
{
	if(picked == 3)
	{
		for(int i=0;i<3;++i) cout << processed[i];
		cout << endl;
		return;
	}
	else
	{
		//5-3+picked是最右能到哪里，如果非常靠右，那么后面的数字就选不够了！
		for(int i=start;i<=5-3+picked;++i)
		{
			processed[picked] = num[i];
			combination(i+1,picked+1);
		}
	}
}
int main()
{
	combination(0,0);
	return 0;
}