RT，代码：

#include <algorithm>
#include <cstdio>
#include <vector>
#include <queue>
using namespace std;
const int N = 100005;
struct Edge {
	int v, w, next;
} edge[8 * N];
int head[2 * N];
int cnt;
void add_edge(int u, int v, int w) {
	cnt++;
	edge[cnt].v = v;
	edge[cnt].w = w;
	edge[cnt].next = head[u];
	head[u] = cnt;
}
int x[N], y[N], dis[2 * N];
vector < int > x_point[N], y_point[N];
bool cmpx(int u, int v) {
	return x[u] > x[v];
}
bool cmpy(int u, int v) {
	return y[u] > y[v];
}
struct Vertex {
	int u, dis;
	Vertex(int u_, int dis_) {
		u = u_;
		dis = dis_;
	}
};
bool operator < (const Vertex & a, const Vertex & b) {
	return a.dis > b.dis;
}
int min(int a, int b) {
	return a < b ? a : b;
}
int main() {
	int n, m;
	scanf("%d %d", &n, &m);
	for (int i = 1; i <= m + 2; i++) {
		scanf("%d %d", &x[i], &y[i]);
		x_point[x[i]].push_back(i);
		y_point[y[i]].push_back(i);
	}
	for (int i = 1; i <= m; i++) {
		add_edge(i, i + m + 2, 1);
		add_edge(i + m + 2, i, 1);
	}
	add_edge(m + 1, 2 * m + 3, 0);
	add_edge(2 * m + 3, m + 1, 0);
	add_edge(m + 2, 2 * m + 4, 0);
	add_edge(2 * m + 4, m + 2, 0);
	for (int u, v, i = 1; i <= n; i++) {
		sort(x_point[i].begin(), x_point[i].end(), cmpy);
		for (int j = 0; j < (int)x_point[i].size() - 1; j++) {
			u = x_point[i][j];
			v = x_point[i][j + 1];
			add_edge(u, v, 2 * (y[u] - y[v]));
			add_edge(v, u, 2 * (y[u] - y[v]));
		}
		sort(y_point[i].begin(), y_point[i].end(), cmpx);
		for (int j = 0; j < (int)y_point[i].size() - 1; j++) {
			u = y_point[i][j];
			v = y_point[i][j + 1];
			add_edge(u + m + 2, v + m + 2, 2 * (x[u] - x[v]));
			add_edge(v + m + 2, u + m + 2, 2 * (x[u] - x[v]));
		}
	}
	for (int i = 1; i <= 2 * m + 4; i++) {
		dis[i] = 0x7fffffff;
	}
	priority_queue < Vertex > q;
	dis[m + 1] = 0;
	q.push(Vertex(m + 1, 0));
	while (!q.empty()) {
		int u = q.top().u;
		q.pop();
		if (q.top().dis != dis[u]) {
			continue;
		}
		for (int v, i = head[u]; i != 0; i = edge[i].next) {
			v = edge[i].v;
			if (dis[v] > dis[u] + edge[i].w) {
				dis[v] = dis[u] + edge[i].w;
				q.push(Vertex(v, dis[v]));
			}
		}
	}
	printf("%d", dis[m + 2]);
	return 0;
}