pku1011 Sticks

一直没想好怎么搜索，所以一直没写，最近看到一段细节写得非常好的代码，于是把这道题AC了，感觉这段搜索写得灰常强大，短而效率高

#include <cstdio>
#include <algorithm>
#include <functional>
using namespace std;

const int maxN = 64 + 5;
int n, stick[maxN], len, m;
bool used[maxN] = {false}, done;

void dfs(int k, int now, int cnt)
{
	if (cnt == m)
		done = true;
	else if (now == len)
		dfs(0, 0, cnt + 1);
	else {
		int pre = -1;
		for (int i = k; i < n; ++i)
			if (!used[i] && stick[i] != pre && now + stick[i] <= len)
			{
				used[i] = true;
				pre = stick[i];
				dfs(k + 1, now + stick[i], cnt);
				used[i] = false;
				if (k == 0 || done)
					return;
			}
	}
}

int main()
{
	while (scanf("%d", &n), n > 0)
	{
		int sum = 0;
		for (int i = 0; i < n; ++i)
		{
			scanf("%d", &stick[i]);
			sum += stick[i];
		}
		sort(stick, stick + n, greater<int>());
		done = false;
		for (len = stick[0]; len <= sum; ++len)
			if (sum % len == 0)
			{
				m = sum / len;
				dfs(0, 0, 0);
				if (done)
					break;
			}
		printf("%d\n", len);
	}
	return 0;
}

原代码的地址是
http://www.cnblogs.com/lotus3x/archive/2008/07/25/1251552.html