> #include<iostream>
> using namespace std;
> 
> int main()
> {
> 	freopen("in.txt", "r", stdin);
> 	char a, c, b, d;
> 	int i;
> 	int begin_i, end_i, begin_j, end_j;         
> 	int Row[65];
> 	int Col[65];
> 	int row, col;
> 	int rear, front, temp, que[65];
> 	int visit[65][65];
> 	int move[8][2] = {{-2, -1}, {-2, 1}, {-1, -2}, {-1, 2}, {1, -2}, {1, 2}, {2, -1}, {2, 1}};
> 	while(cin >> a >> b >> c >> d) {     //输入方式有诸多疑问
> 		begin_i = a - 'a', begin_j = b - '1', end_i = c - 'a', end_j = d - '1'; 
> 		for(i = 0; i < 8; i ++)
> 			for(int j = 0; j < 8; j ++)
> 				visit[i][j] = 0;                   //非要这样写？memset不行？？？？？？？
> 		//memset(visit, 0, sizeof(0));           //天呐天呐 谁告诉我为什么这行不行！！！！！！！！！！！！！！！！！1
> 		front = rear = 0;
> 		Row[0] = begin_i;
> 		Col[0] = begin_j;
> 		que[rear ++] = 0;
> 		visit[begin_i][begin_j] = 1;
> 		while(front < rear) {
> 			temp = front ++;
> 			if(Row[temp] == end_i && Col[temp] == end_j) 
> 				break;
> 			for(i = 0; i < 8; i ++) {
> 				row = Row[temp] + move[i][0];
> 				col = Col[temp] + move[i][1];
> 				if(row >= 0 && col >= 0 && row < 8 && col < 8 && visit[row][col] == 0) {         
> 					visit[row][col] = 1;
> 					Row[rear] = row;
> 					Col[rear] = col;
> 					que[rear ++] = que[temp] + 1;
> 					//cout << temp << endl;
> 				}
> 			}
> 		}
> 		cout << que[temp] << endl;
> 	}
> 	return 0;
> }