求助链式前向星写法

#include<bitset>
#include<queue>
#include<iostream>
#include<cstring>
#include<cstdio>
#define inf 2147483647
using namespace std;
const int N = 1e6 + 10;
struct Edge {
	int to, w, next;
} edge[N];
struct PE {
	int to, dis;
	bool operator<(const PE &e)const {
		return dis < e.dis;
	}
};
int cntEdge, head[N], dist[N];
bitset<N> vis;
void insert(int u, int v, int w) {
	edge[++cntEdge].to = v;
	edge[cntEdge].w = w;
	edge[cntEdge].next = head[u];
	head[u] = cntEdge;
	return;
}
int n, m, starter;
priority_queue<PE> q;
void dijkstra() {
	for (int i = 0; i <= n; i++) {
		dist[i] = inf;
	}
	dist[starter] = 0;
	q.push((PE){starter, dist[starter]});
	while (!q.empty()) {
		PE top = q.top();
		q.pop();
		int x = top.to;
		if (vis[x])
			continue;
		vis[x] = 1;
		for (int i = head[x]; i; i = edge[i].next) {
			int to = edge[i].to, w = edge[i].w;
			if (dist[x] + w < dist[to]) {
				dist[to] = dist[x] + w;
				if (!vis[to])
				q.push((PE) {to, dist[to]});
			}
		}
	}
}
int main() {
	scanf("%d%d%d", &n, &m, &starter);
	for (int i = 1, u, v, w; i <= m; i++) {
		scanf("%d%d%d", &u, &v, &w);
		insert(u, v, w);
	}
	dijkstra();
	for (int i = 1; i <= n; i++) {
		printf("%d ", dist[i]);
	}
	return 0;
}