华为 第二题 跳马 80%
// 感觉是没有考虑到边界情况,不是超时,是答案错误。不过感觉可以dp优化下,dfs纯暴搜确实捞 import java.util.Scanner; public class Main { static int m, n; static long[][][] PATH; static char[][] board; public static void main(String[] args) { Scanner sc = new Scanner(System.in); m = sc.nextInt(); n = sc.nextInt(); sc.nextLine(); board = new char[m][n]; for (int i = 0; i < m; i++) { String s = sc.nextLine(); board[i] = s.toCharArray(); } PATH = new long[m][n][2]; for (int i = 0; i < m; i++) { for (int j = 0; j < n; j++) { PATH[i][j][0] = Integer.MAX_VALUE; PATH[i][j][1] = Integer.MAX_VALUE; } } dfs(0, 0, 0, 0); System.out.println(Math.min(PATH[m-1][n-1][0],PATH[m-1][n-1][1]) >= Integer.MAX_VALUE ? -1 : Math.min(PATH[m-1][n-1][0],PATH[m-1][n-1][1])); } public static void dfs(int state, int i, int j, int path){ if (i >= 0 && j >= 0 && i < m && j < n && path < PATH[i][j][state] && board[i][j] != 'X') { PATH[i][j][state] = path; if (state == 0) { dfs(state, i + 1, j, path + 1); dfs(state, i , j+ 1, path + 1); } if (state == 1) { dfs(state, i-2, j+1, path+1); dfs(state, i+1, j+2, path+1); dfs(state, i+1, j-2, path+1); dfs(state, i+2, j+1, path+1); dfs(state, i+2, j-1, path+1); } if (board[i][j] == 'S'){ state = toggle(state); path++; if (state == 0) { dfs(state, i + 1, j, path + 1); dfs(state, i , j+ 1, path + 1); } if (state == 1) { dfs(state, i-2, j+1, path+1); dfs(state, i+1, j+2, path+1); dfs(state, i+2, j+1, path+1); } } } } static int toggle(int x) { return x == 0 ? 1 : 0; } }
#华为#