剑指Offer12 矩阵中的路径（有趣的题）

Posted 2021-10-24 小布丁value

参考文献https://leetcode-cn.com/problems/ju-zhen-zhong-de-lu-jing-lcof/

public class Day1005 {
    public static void main(String[] args) {

    }
    public boolean exist(char [][] board,String word){
        char[] words=word.toCharArray();
        for(int i=0;i<board.length;i++){
            for(int j=0;j<board[0].length;j++){
               if (dfs(board,words,i,j,0)) return true;
            }
        }
        return false;
    }
    boolean dfs(char[][] board,char[] words,int i,int j,int k){
        //剪掉边界和不想等字符
        if(i>board.length-1||i<0||j>board[0].length-1||j<0||board[i][j]!=words[k]) return false;
        //走到目标数组的末尾
        if(k==words.length-1) return true;
        //走过（相等的字符）的数标记出来，防止重复
        board [i][j]= '\\0';
        //按照下，上，右，左，深度遍历的方式走
        boolean res=(dfs(board,words,i+1,j,k+1)||dfs(board,words,i-1,j,k+1)||dfs(board,words,i,j+1,k+1)||
                dfs(board,words,i,j-1,k+1));
        //走成功或者没成功，最后都要把人家的数返回回来
        board[i][j]=words[k];
        return res;
    }


}