#include<bits/stdc++.h>
using namespace std;
int hx, hy, vis[25][25], ans = 1e9, dx[20] = {1, 1, 2, 2, 2, 2, -1, -1, -2, -2, -2, -2}, dy[20] = {-2, 2, -2, -1, 1, 2, -2, 2, -1, 1, -2, 2};
struct node{
	int x, y, step;
	node(int ax = 0, int ay = 0, int astep = 0) {
		x = ax, y = ay, step = astep;
	}
};
void bfs(int x, int y, int step) {
	queue<node> q;
	q.push(node(x, y, step));
	while(!q.empty()) {
		node fro = q.front();
		q.pop();
		int nx = fro.x, ny = fro.y, nstep = fro.step;
		if(nx == 1 && ny == 1) {
			ans = min(nstep, ans);
			//cout << endl << endl;
			continue;
		}
		if(nx < 1 || ny < 1 || nx > 20 || ny > 20) continue;
		if(vis[nx][ny]) continue;
		vis[nx][ny] = 1;
		//cout << nx << " " << ny << endl;
		for (int i = 0; i < 12; i++) {
			q.push(node(nx + dx[i], ny + dy[i], nstep + 1));
		}
	}
}
int main(void) {
	cin >> hx >> hy;
	//vis[hx][hy] = 1;
	bfs(hx, hy, 0);
	cout << ans << endl;
	ans = 1e9;
	memset(vis, 0, sizeof(vis));
	//vis[hx][hy] = 1;
	cin >> hx >> hy;
	bfs(hx, hy, 0);
	cout << ans;
 	return 0;
}

手输和复制两种都能正常返回值， 求dalao解答。