leetcode算法题--机器人的运动范围

原题链接：https://leetcode.cn/problems/ji-qi-ren-de-yun-dong-fan-wei-lcof/description/?envType=study-plan-v2&envId=coding-interviews

func movingCount(m int, n int, k int) int {
    blocks := make([][]int, m)
    visited := make([][]int, m)
    for i := range blocks {
        blocks[i] = make([]int, n)
        visited[i] = make([]int, n)
        for j := 0; j < n; j ++ {
            blocks[i][j] = -1
            visited[i][j] = -1
            if getSum(i) + getSum(j) > k {
                blocks[i][j] = 1
            }
        }
    }
    var dfs func(i, j int) int 
    dfs = func(i, j int) int {
        res := 0 
        dirs := [][]int{{0, 1}, {1, 0}, {0, -1}, {-1, 0}}
        if blocks[i][j] != 0 {
           res = 1 
        }
        blocks[i][j] = 0
        visited[i][j] = 1
        for _, dir := range dirs {
            x := i + dir[0]
            y := j + dir[1]
            if x >= 0 && x < m && y >= 0 && y < n && visited[x][y] != 1 && blocks[x][y] == -1 {
                res += dfs(x, y)
            }
        }
        visited[i][j] = -1 
        return res
    }
    return dfs(0, 0)
}

func getSum(num int) int {
    sum := 0
    for num != 0{
        r := num % 10
        sum += r
        num /= 10
    }
    return sum
}

只是求机器人的运动范围，只用从右或者从下走就可以了，并且visited也不需要还原

func movingCount(m int, n int, k int) int {
    blocks := make([][]int, m)
    // visited := make([][]int, m)
    for i := range blocks {
        blocks[i] = make([]int, n)
        // visited[i] = make([]int, n)
        for j := 0; j < n; j ++ {
            blocks[i][j] = -1
            // visited[i][j] = -1
            if getSum(i) + getSum(j) > k {
                blocks[i][j] = 1
            }
        }
    }
    var dfs func(i, j int) int 
    dfs = func(i, j int) int {
        res := 0 
        // dirs := [][]int{{0, 1}, {1, 0}, {0, -1}, {-1, 0}}
        dirs := [][]int{{0, 1}, {1, 0}}
        if blocks[i][j] != 0 {
           res = 1 
        }
        blocks[i][j] = 0
        //visited[i][j] = 1
        for _, dir := range dirs {
            x := i + dir[0]
            y := j + dir[1]
            // if x >= 0 && x < m && y >= 0 && y < n && visited[x][y] != 1 && blocks[x][y] == -1 {
            if x >= 0 && x < m && y >= 0 && y < n && blocks[x][y] == -1 {
                res += dfs(x, y)
            }
        }
        //visited[i][j] = -1 
        return res
    }
    return dfs(0, 0)
}

func getSum(num int) int {
    sum := 0
    for num != 0{
        r := num % 10
        sum += r
        num /= 10
    }
    return sum
}