单词搜索-

const int N = 20;

int dx\[\] = {0, 0, 1, -1};

int dy\[\] = {1, -1, 0, 0};

class Solution {

public:

bool dfs(int i, int j, int n, int m, vector<vector<char>>& board,

string& word, vector<vector<bool>>& st, int cnt) {

if (boardij != wordcnt)

return false;

if (cnt == word.size()-1)

return true;

stij=true;

for (int k = 0; k < 4; ++k) {

int x = dxk + i, y = dyk + j;

if (x < 0 || x >= n || y < 0 || y >= m || stxy)

continue;

if (

dfs(x, y, n, m, board, word, st, cnt+1))

return true;

}

stij=false;

return false;

}

bool exist(vector<vector<char>>& board, string word) {

int n = board.size(), m = board0.size();

string path;

for (int i = 0; i < n; ++i) {

for (int j = 0; j < m; ++j) {

vector<vector<bool>> st(n, vector<bool>(m, false));

if (boardij == word0 &&dfs(i, j, n, m, board, word, st, 0))

return true;

}

}

return false;

}

};