题解 | #童谣寻找问题#

/**
 * 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
 *
 *
 * @param board char字符型二维数组
 * @param boardRowLen int board数组行数
 * @param boardColLen int* board数组列数
 * @param word string字符串
 * @return bool布尔型
 */
void dfs(char** board, int m, int n, int i, int j, int current, char* word,
         int* flag, int** visited) {
    if (i < 0 || i >= m || j < 0 || j >= n || board[i][j] != word[current] ||
            visited[i][j] == 1) return;
    if (current + 1 == strlen(word) && board[i][j] == word[current]) {
        (*flag) = 1;
        return;
    }
    visited[i][j] = 1;
    dfs(board, m, n, i + 1, j, current + 1, word, flag, visited);
    dfs(board, m, n, i - 1, j, current + 1, word, flag, visited);
    dfs(board, m, n, i, j - 1, current + 1, word, flag, visited);
    dfs(board, m, n, i, j + 1, current + 1, word, flag, visited);
    visited[i][j] = 0;
}
bool exist(char** board, int boardRowLen, int* boardColLen, char* word ) {
    // write code here
    int len = strlen(word);
    int current = 0;
    int m = boardRowLen, n = boardColLen[0];
    int** visited = malloc(sizeof(int*)*m);
    for (int i = 0; i < m; i++) {
        visited[i] = malloc(sizeof(int) * n);
        for (int j = 0; j < n; j++) {
            visited[i][j] = 0;
        }
    }
    for (int i = 0; i < m; i++) {
        for (int j = 0; j < n; j++) {
            if (board[i][j] == word[0]) {
                int flag = 0;
                dfs(board, m, n, i, j, current, word, &flag, visited);
                if (flag) return true;
            }
        }
    }
    return false;
}