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将点权为1的插入对尾，为0的插入队头

拖拉机

#include<iostream>
#include<algorithm>
#include<cstring>
#include<deque>

using namespace std;

const int N = 2010;
typedef pair<int,int> p;

int dist[N][N];
int d[N][N];

int n,x0,y0;

void bfs(){
    memset(dist,0x3f,sizeof dist);
    deque<p> q;

    q.push_back({x0,y0});
    dist[x0][y0] = 0;

    int dx[4] = {0,1,0,-1},dy[4] = {-1,0,1,0};

    while(q.size()){
        p t = q.front();
        q.pop_front();
        
        for(int i = 0;i < 4;i ++){
            int x = t.first + dx[i],y = t.second + dy[i];

            if(x < 0 || y < 0 || x > 1003 || y > 1003) continue;

            if(dist[x][y] > dist[t.first][t.second] + d[x][y]){
                dist[x][y] = dist[t.first][t.second] + d[x][y];
                if(d[x][y]) q.push_back({x,y});
                else q.push_front({x,y});
            }
        }
    }
}

int main(){
    cin >> n >> x0 >> y0;

    for(int i = 0;i < n;i ++){
        int a,b;
        cin >> a >> b;

        d[a][b] = 1;
    }

    bfs();

    cout << dist[0][0];
}