1053. Path of Equal Weight

经典的树的遍历问题，在插入每个非叶节点的邻接点时，维护一个优先队列，优先插入数据比较大的节点，从而在实施搜索时一旦碰到叶子节点，且该路径上数据总和为所需值时，直接输出该路径上的各数据。

// 1053. Path of Equal Weight.cpp: 主项目文件。#include "stdafx.h"#include <cstdio>#include <cstring>#include <vector>#include <queue>using namespace std;const int N=103;int hashTable[N];bool used[N];int needSum;typedef struct Node{int flag,data;}Node;struct cmp{bool operator()(Node m1,Node m2){return m1.data<m2.data;}};vector<Node> edge[N]; priority_queue<Node,vector<Node>,cmp> Q;vector<Node> path;void dfs(int cur,int curSum){used[cur]=true;if(edge[cur].size()==0&&curSum==needSum){for(vector<Node>::iterator ite=path.begin();ite!=path.end();ite++){if(ite!=path.begin())printf(" ");printf("%d",ite->data);}printf("\n");}for(vector<Node>::iterator ite=edge[cur].begin();ite!=edge[cur].end();ite++){if(!used[ite->flag]){path.push_back(*ite);dfs(ite->flag,curSum+ite->data);path.pop_back();}}}int main(){int nodes,nonLeafNodes;scanf("%d%d%d",&nodes,&nonLeafNodes,&needSum);for(int i=0;i<nodes;i++)scanf("%d",hashTable+i);for(int i=0;i<nonLeafNodes;i++){int from,num;scanf("%d%d",&from,&num);while(!Q.empty())Q.pop();while(num--){int tFlag,tData;scanf("%d",&tFlag);tData=hashTable[tFlag];Node node;node.flag=tFlag,node.data=tData;Q.push(node);}while(!Q.empty()){Node tNode=Q.top();edge[from].push_back(tNode);Q.pop();}}memset(used,0,sizeof(used));Node root;root.flag=0,root.data=hashTable[0];path.push_back(root);dfs(0,hashTable[0]);    return 0;}