题目描述
地上有一个m行和n列的方格。一个机器人从坐标0,0的格子开始移动,每一次只能向左,右,上,下四个方向移动一格,但是不能进入行坐标和列坐标的数位之和大于k的格子。 例如,当k为18时,机器人能够进入方格(35,37),因为3+5+3+7 = 18。但是,它不能进入方格(35,38),因为3+5+3+8 = 19。请问该机器人能够达到多少个格子?
分析
跑一遍DFS并计数。
# -*- coding:utf-8 -*-
class Solution:
def __init__(self):
self.count = 0
def movingCount(self, threshold, rows, cols):
# write code here
if rows + cols == 2:
return 1
def getSum(x):
sum = 0
while x >= 10:
sum = sum + x % 10
x = x // 10
sum = sum + x
return sum
def judge(r, c):
if r < 0 or c < 0 or r >= rows or c >= cols or vis[r][c] == 1:
return False
if getSum(r) + getSum(c) <= threshold:
return True
else:
return False
def dfs(r, c):
for i in range(4):
if judge(r + tx[i], c + ty[i]):
vis[r + tx[i]][c + ty[i]] = 1
self.count += 1
dfs(r + tx[i], c + ty[i])
vis = [ [0] * cols for i in range(rows)]
tx = [0, 0, 1, -1]
ty = [1, -1, 0, 0]
dfs(0, 0)
return self.count
1. 开二维数组
vis = [ [0] * cols for i in range(rows)]
2. 计算一个数的所有位数之和
tmpx = list(map(int, list(str(x)))) sumx = sum(tmpx)