堆优化 dijkstra +路径输出

#include <iostream>
#include <cstdio>
#include <algorithm>
#include <queue>
#include <bits/stdc++.h>

using namespace std;
const int N = 10010;
const int oo = 99999999;

int dis[N], pre[N];
bool vis[N];
int n, m, S;
struct Node{
	int u, v, w;
	Node(int u, int v, int w):u(u), v(v), w(w) {}
};
struct Headnode{
	int dis_this, u;
	bool operator < (const Headnode& now) const
	{
		return dis_this > now.dis_this;
	}
};
vector <int> G[N];
vector <Node> EE;

inline int read()
{
	int x = 0; char c = getchar();
	while(c < '0' || c > '9')c = getchar();
	while(c >= '0' && c <= '9')x = x * 10 + c - '0', c = getchar();
	return x;
}

inline void dijkstra(int start)
{
	priority_queue <Headnode> Q;
	for(int i = 1; i <= n; i ++)
		dis[i] = oo;
	dis[start] = 0;
	memset(vis, 0, sizeof(vis));
	Headnode HHH;
	HHH.dis_this = 0;
	HHH.u = start;
	Q.push(HHH);
	while(!Q.empty())
	{
		Headnode topp = Q.top();
		Q.pop();
		int u = topp.u;
		if(vis[u])
			continue;
		for(int i = 0; i < G[u].size(); i ++)
		{
			Node e = EE[G[u][i]];
			if(dis[e.v] > dis[u] + e.w)
			{
				dis[e.v] = dis[u] + e.w;
				pre[e.v] = G[u][i];
				Q.push((Headnode) {dis[e.v], e.v});
			}
		}
	}
}

inline void add(int u,int v,int w)
{
	EE.push_back(Node(u, v, w));
	G[u].push_back(EE.size() - 1);
}

int main()
{
	n = read();
	m = read();
	S = 1;
	
	for(int i = 1; i <= m; i ++)
	{
		int u = read();
		int v = read();
		int w = read();
		add(u, v, w);
	}
	dijkstra(S);
	while(1)
	{
		int endd = read();
		printf("%d",dis[endd]);
	}
	return 0;
}
/*
5 7
1 2 4
1 3 6
1 5 50
2 3 5
3 5 7
3 4 8
4 5 9
*/