题解【鸟哥哥js】 | #岛屿数量#

/**
 * 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
 *
 * 判断岛屿数量
 * @param grid char字符型二维数组
 * @return int整型
 */
let isValid = (grid, r, c) => {
    return r >= 0 && r < grid.length && c < grid[0].length && c >= 0;
};
let dfs = (grid, r, c) => {
    if (!isValid(grid, r, c) || grid[r][c] != "1") {
        return;
    }
    grid[r][c] = "2";
    dfs(grid, r - 1, c);
    dfs(grid, r + 1, c);
    dfs(grid, r, c - 1);
    dfs(grid, r, c + 1);
};
function solve(grid) {
    // write code here
    let count = 0;
    let r = grid.length - 1;
    let c = grid[0].length - 1;
    for (let i = 0; i <= r; i++) {
        for (let j = 0; j <= c; j++) {
            if (grid[i][j] === "1") {
                dfs(grid, i, j);
                count = count + 1;
            }
        }
    }

    return count;
}
module.exports = {
    solve: solve,
};