> #include<iostream>
> #include<stdlib.h>
> #include<memory.h>
> using namespace std;
> int n;
> int stick[65];
> int len;
> int sumlen=0;
> bool used[65];
> int nLastStickNo=0;
> bool DFS(int UnusedStick ,int left )
> {
> if(UnusedStick==0&&left==0)
> 	return true;
> if(left==0)
> 	left=len;
> int nStartNo = 0;
> 	if( left != len) //剪枝
> 		nStartNo = nLastStickNo + 1;
> 
> for(int i = nStartNo;i < n;i ++)
> {
> 	if(!used[i]&&stick[i]<=left)
> 	{
> 		if(i>0)
> 		{
> 			if(used[i-1]==0&&stick[i]==stick[i-1])
> 				continue;
> 		}
> 		used[i]=true;
> 		nLastStickNo = i;
> 		if(DFS(UnusedStick-1,left-stick[i]))
> 			return true;
> 		else
> 			{
> 			used[i]=false;
> 			if(stick[i]==left||left==len)//剪枝
> 				return false;
> 			}
> }
> }
> return false;
> }
> 
> int compare(const void*x,const void *y)
> {
> return *(int*)y- *(int*)x;
> }
> 
> int main()
> {
> 	while(true)
> 	{
> 	cin>>n;
> 	if(n==0)
> 	break;
> 	int i,j;
> 	for(i=0;i<n;i++)
> 	{
> 		cin>>stick[i];
> 		sumlen+=stick[i];
> 	}
> 	qsort(stick,n,sizeof(int),compare);
> 
> 	if(stick[0]>(sumlen/2))
> 		cout<<sumlen<<endl;//一个优化
> 
> 	for(len=stick[0];len<=sumlen/2;len++)
> 	{
> 		if(sumlen%len)
> 			continue;
> 		memset( used, 0,sizeof(used));
> 		if(DFS(n,len))
> 			{
> 			cout<<len<<endl;
> 			break;
> 			}
> 
> 	}
> memset(stick,0,sizeof(stick));
> sumlen=0;
> memset( used, 0,sizeof(used));
> len=0;
> 	}
> 	return 0;
> }


我把已知的数据都测试了……没有问题