LeetCode--Word Search

dfs

https://github.com/cane1991/BasicAlogrithmSourceCode/blob/master/LeetCode/WordSearch.cpp

/*************************************************************************
    > File Name: WordSearch.cpp
    > Author: zhoukang1991
    > Mail: zhoukang199191@126.com 
    > Created Time: 2014年08月14日 星期四 00时58分49秒
 ************************************************************************/

#include <iostream>
#include <vector>
#include <string>
using namespace std;

class Solution{
    public:
        bool exist(vector<vector<char> > &board,string word){
            const int row = board.size();
            if(row == 0)
                return false;
            const int col = board[0].size();
            for(int i = 0 ; i < row ; ++i){
                for(int j = 0 ; j < col ; ++j){
                    if(board[i][j] == word[0] && dfs(i,j,word,0,board))
                        return true;
                }
            }
            return false;
        }
        bool dfs(int row,int col,string &word,int index,vector<vector<char> > &board){
            if(index = word.size()-1)
                return true;
            char ctmp = board[row][col];
            board[row][col] = '.';

            //left right up down dfs
            if(col-1 >= 0 && board[row][col-1] == word[index+1]){
                if(dfs(row,col-1,word,index+1,board)){
                    return true;
                }
            }
            if(col+1 <= board[0].size() && board[row][col+1] == word[index+1]){
                if(dfs(row,col+1,word,index+1,board)){
                    return true;
                }
            }
            if(row-1 >= 0 && board[row-1][col] == word[index+1]){
                if(dfs(row-1,col,word,index+1,board))
                    return true;
            }
            if(row+1 <= board[0].size() && board[row+1][col] == word[index+1]){
                if(dfs(row+1,col,word,index+1,board))
                    return true;
            }
        }
};

int main()
{
    return 0;
}