堆优化邻接表dijkstra算法，c++，单源最短路

#include <bits/stdc++.h>

using namespace std;

#define endl '\n'
// #define int long long
using u32 = unsigned;
using i64 = long long;
using u64 = unsigned long long;
using PII = pair<int, int>;
const int INF = 0x3f3f3f3f;

int n,m;

int dijkstra(vector<vector<PII>>&graph){
	vector<int>dist(n+1,INF);
	
	priority_queue<PII,vector<PII>,greater<PII>>pq;
	pq.push({0,1});
	dist[1]=0;
	
	while(!pq.empty()){
		auto top=pq.top();
		pq.pop();
		auto d=top.first,u=top.second;
		
		if(d>dist[u])continue;
		
		for(auto &i:graph[u]){
			auto v=i.first,w=i.second;
			if(dist[v]>dist[u]+w){
				dist[v]=dist[u]+w;
				pq.push({dist[v],v});
			}
		}
	}

}

void solve(){
	
	cin>>n>>m;
	vector<vector<PII>>graph(n+1);
	int u,v,w;
	for(int i=1;i<=m;i++){
		cin>>u>>v>>w;
		graph[u].push_back({v,w});
	}
	
	dijkstra(graph);
	
}

signed main(){
	ios::sync_with_stdio(0);
	cin.tie(0);
	solve();
	return 0;
}