Question link: http://poj.org/problem? Id = 2288
Each vertex has a weight VI and finds a Hamilton path. The weight of the path comes from three: 1. The sum of VI in the path 2 the sum of VI * VJ of all adjacent points to IJ 3 the sum of VI * VJ * VK of adjacent three consecutive I, j, and K (and the three points must form a triangle.
Solution: DP [st] [I] [J] indicates the maximum weight from J to I and the rest of the Set st is not taken. The path book can be computed by the way during the transfer. This question has been disgusting for a long time. The final reason is that you have made a serious mistake and read the wrong question, if you do not read VI * VJ * VK, you must ensure that ijk can form a triangle and check whether ik has edges by modifying the code. Of course, pay attention to the situations where the number of paths may exceed int and a specific point;
Code:
/******************************************************* @author:xiefubao*******************************************************/#pragma comment(linker, "/STACK:102400000,102400000")#include <iostream>#include <cstring>#include <cstdlib>#include <cstdio>#include <queue>#include <vector>#include <algorithm>#include <cmath>#include <map>#include <set>#include <stack>#include <string.h>//freopen ("in.txt" , "r" , stdin);using namespace std;#define eps 1e-8#define zero(_) (abs(_)<=eps)const double pi=acos(-1.0);typedef long long LL;const int Max=14;const int INF=1e9+7;int num[Max];LL dp[1<<Max][Max][Max];LL cnt[1<<Max][Max][Max];bool rem[Max][Max];vector<int> vec[Max];int n,m;LL getdp(int st,int i,int j){ if(dp[st][i][j]!=-1) return dp[st][i][j]; LL ans=-INF; LL sum=0; for(int l=0; l<vec[i].size(); l++) { int k=vec[i][l]; if((st&(1<<k))==0) continue; if() LL tool=getdp(st-(1<<k),k,i)+num[k]*num[i]+num[k]*num[i]*num[j]; if(tool==ans) sum+=cnt[st-(1<<k)][k][i]; if(tool>ans) { sum=cnt[st-(1<<k)][k][i]; ans=tool; } } cnt[st][i][j]=sum; return dp[st][i][j]=ans;}int main(){ int t; cin>>t; while(t--) { memset(rem,0,sizeof rem); scanf("%d%d",&n,&m); int sum=0; for(int i=0; i<n; i++) scanf("%d",num+i),sum+=num[i],vec[i].clear(); for(int i=0; i<m; i++) { int a,b; scanf("%d%d",&a,&b); a--,b--; if(a==b) continue; vec[a].push_back(b); vec[b].push_back(a); rem[a][b]=1; rem[b][a]=1; } if(n==1) { printf("%d %d\n",num[0],1); continue; } memset(dp,-1,sizeof dp); memset(cnt,0,sizeof cnt); for(int i=0; i<n; i++) for(int j=0; j<n; j++) { dp[0][i][j]=-INF; if(!rem[i][j])continue; dp[0][i][j]=0; cnt[0][i][j]=1; } LL ans=-INF; LL out=0; for(int i=0; i<n; i++) for(int j=0; j<n; j++) { if(!rem[i][j]) continue; LL tool=getdp((1<<n)-(1<<i)-(1<<j)-1,i,j)+num[i]*num[j]; if(ans==tool) out+=cnt[(1<<n)-(1<<i)-(1<<j)-1][i][j]; if(ans<tool) { ans=tool; out=cnt[(1<<n)-(1<<i)-(1<<j)-1][i][j]; } } if(out==0||ans<=0) printf("0 0\n"); else cout<<ans+sum<<" "<<out/2<<endl; } return 0;}/*6 151 1 1 1 1 11 21 31 41 51 62 32 42 52 63 43 53 64 54 65 6*/