做的POJ的一些题目

				#include
				using namespace std;
				typedef struct
				{
				     int v;
				     int left;
				     int right;
				     bool visit;       
				}node;
				int n,best=100000000;
				void f(node mg[100],int sum,int k)
				{
				     if(sum>=best)
				        return;
				     if(k==n-2)
				     {
				         if(sum				           best=sum;
				           return;          
				     }
				     for(int i=1;i				     {
				          if(mg[i].visit==false)
				          {
				               mg[i].visit=true;
				               mg[mg[i].left].right=mg[i].right;
				               mg[mg[i].right].left=mg[i].left;
				               f(mg,sum+mg[i].v*mg[mg[i].left].v*mg[mg[i].right].v,k+1);
				               mg[i].visit=false;
				               mg[mg[i].left].right=i;
				               mg[mg[i].right].left=i;                      
				          }        
				     }
				}
				int main()
				{
				    scanf("%d",&n);
				    node mg[n];
				    scanf("%d",&mg[0].v);
				    for(int i=1;i				    {
				         scanf("%d",&mg[i].v);
				         mg[i].left=i-1;
				         mg[i-1].right=i;    
				         mg[i].visit=false;    
				    }
				    f(mg,0,0);
				    printf("%d\n",best);
				    system("pause");
				    return 0;
				}