本人代码提交后洛谷显示TLE,下载数据#1后自测很快输出答案未停顿(大约就是平常的2ms)是什么原因？算法是dijkstra+优先队列。

相关信息：

• 编译器：Start Experimental Instance of Visual Studio 2019
• P5767 [NOI1997] 最优乘车
• 评测记录https://www.luogu.com.cn/record/56926221
  附上代码：

#include<iostream>
#include<cstdio>
#include<cmath>
#include<queue>
#include<cstring>
#define N 500 + 10
#define M 100 + 10
#define EDGE ((N * (N - 1)) >> 1) * M
using namespace std;
int m, n, station[N], stationadd, cnt, road, head[N], ans, v[N];
bool vis[N];
struct edgenode {	int road, nextstation, nextedge;};
edgenode edge[EDGE];
inline int read() {
	int s = 0, w = 1;
	char ch = getchar();
	while (ch < '0' || ch>'9') {
		if (ch == '-') w = -1;
		ch = getchar();
	}
	while (ch >= '0' && ch <= '9') {
		s = (s << 3) + (s << 1) + (ch ^ 48);
		ch = getchar();
	}
	return s * w;
}
void buildedge() {
	++road;
	for (int i = 1; i < stationadd; ++i) {
		for (int j = i + 1; j <= stationadd; ++j) {
			edge[++cnt].road = road;
			edge[cnt].nextstation = station[j];
			edge[cnt].nextedge = head[station[i]];
			head[station[i]] = cnt;
		}
	}
}
void readline() {
	//int x=read();//没有什么用
	stationadd = 0;
	char ch = getchar();
	while (ch != '\n') {
		int s = 0, w = 1;
		while (ch < '0' || ch>'9') {
			if (ch == '-') w = -1;
			ch = getchar();
		}
		while (ch >= '0' && ch <= '9') {
			s = (s << 3) + (s << 1) + (ch ^ 48);
			ch = getchar();
		}
		station[++stationadd] = s * w;
	}
	buildedge();
}
struct Node {
	int nowstation, road, ans;
	Node(int nowstation, int road, int ans) : nowstation(nowstation), road(road), ans(ans){}
	bool operator<(const Node& x)const {
		return x.ans < ans;
	}
};
int dijkstra() {
	memset(v, 0x3f, sizeof(v));
	priority_queue<Node>q;
	q.push(Node(1, 0, 0));
	v[1] = 0;
	while (!q.empty()) {
		Node u = q.top();
		q.pop();
		if (u.nowstation == n) return u.ans;
		for (int i = head[u.nowstation]; i; i = edge[i].nextedge) {
			if (u.road == 0) {
				if (v[edge[i].nextstation] > v[u.nowstation]) q.push(Node(edge[i].nextstation, edge[i].road, 0)), v[edge[i].nextstation] = v[u.nowstation];
			}
			else {
				if (u.road == edge[i].road && v[edge[i].nextstation] > v[u.nowstation]) q.push(Node(edge[i].nextstation, edge[i].road, u.ans)), v[edge[i].nextstation] = v[u.nowstation];
				else if (u.road != edge[i].road && v[edge[i].nextstation] > v[u.nowstation] + 1) q.push(Node(edge[i].nextstation, edge[i].road, u.ans + 1)), v[edge[i].nextstation] = v[u.nowstation] + 1;
			}
		}
	}
	return -1;
}
int main() {
	m = read(), n = read();
	for (int i = 1; i <= m; ++i) readline();
	ans=dijkstra();
	if (ans != -1) printf("%d", ans);
	else printf("NO");
	return 0;
}