2023-01-14:给定一个二维数组map,代表一个餐厅,其中只有01两种值 map[i][j] == 0 表示(i,j)位置是空座 map[i][j] == 1 表示(i,j)位置坐了人 根据防
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2023-01-14:给定一个二维数组map,代表一个餐厅,其中只有0、1两种值
map[i][j] == 0 表示(i,j)位置是空座
map[i][j] == 1 表示(i,j)位置坐了人
根据防疫要求,任何人的上、下、左、右,四个相邻的方向都不能再坐人
但是为了餐厅利用的最大化,也许还能在不违反防疫要求的情况下,继续安排人吃饭
请返回还能安排的最大人数
如果一开始的状况已经不合法,直接返回-1
比如:
1 0 0 0
0 0 0 1
不违反防疫要求的情况下,这个餐厅最多还能安排2人,如下所示,X是新安排的人
1 0 X 0
0 X 0 1
再比如:
1 0 0 0 0 1
0 0 0 0 0 0
0 1 0 0 0 1
0 0 0 0 0 0
不违反防疫要求的情况下,这个餐厅最多还能安排7人,如下所示,X是新安排的人
1 0 0 X 0 1
0 0 X 0 X 0
0 1 0 X 0 1
X 0 X 0 X 0
数据范围 : 1 <= 矩阵的行、列 <= 20
来自华为。
答案2023-01-14:
轮廓线dp。
代码用solidity和rust编写。
代码用solidity编写。代码如下:
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.17;
contract Hello
function main() public pure returns (int32)
int32[][] memory matrix = new int32[][](2);
for (int32 i = 0; i < 2; i++)
matrix[uint32(i)] = new int32[](2);
for (int32 j = 0; j < 2; j++)
matrix[uint32(i)][uint32(j)] = 0;
//matrix[1][1] = 1;
int32 ans = mostSeats2(matrix);
return ans;
// 正式方法
// 轮廓线dp
function mostSeats2(int32[][] memory map) public pure returns(int32)
int32 n = int32(int(map.length));
int32 m = int32(int(map[0].length));
int32[] memory arr = new int32[](uint32(n));
for (int32 i = 0; i < n; i++)
int32 status = 0;
for (int32 j = 0; j < m; j++)
if (map[uint32(i)][uint32(j)] == 1)
if (i > 0 && map[uint32(i - 1)][uint32(j)] == 1)
return -1;
if (j > 0 && map[uint32(i)][uint32(j - 1)] == 1)
return -1;
status |= map[uint32(i)][uint32(j)] *leftk(j);
arr[uint32(i)] = status;
int32 s = leftk(m);
int32[][][] memory dp = new int32[][][](uint32(n));
for (int32 i = 0; i < n; i++)
dp[uint32(i)] = new int32[][](uint32(m));
for (int32 j = 0; j < m; j++)
dp[uint32(i)][uint32(j)] = new int32[](uint32(s));
for (int32 k = 0; k < s; k++)
dp[uint32(i)][uint32(j)][uint32(k)] = -2;
int32 ans = process2(arr, n, m, 0, 0, 0, dp);
return ans == -1 ? int32(0) : ans;
// 20 * 20 * 2^20 -> 4 * 10^8
function process2(int32[] memory arr, int32 n, int32 m, int32 i, int32 j, int32 status, int32[][][] memory dp) public pure returns (int32)
if (j == m)
return process2(arr, n, m, i + 1, 0, status, dp);
if (i == n)
return 0;
if (dp[uint32(i)][uint32(j)][uint32(status)] != -2)
return dp[uint32(i)][uint32(j)][uint32(status)];
A memory a = A(0,0,0,0,0,0,0);
a.left = status0(status, j - 1, m);
a.up = status0(status, j, m);
a.cur = status0(arr[uint32(i)], j, m);
a.right = status0(arr[uint32(i)], j + 1, m);
if (a.up == 1 && a.cur == 1)
return -1;
a.p1 = -1;
if (a.cur == 1)
a.p1 = process2(arr, n, m, i, j + 1, status | leftk(j), dp);
else
a.p1 = process2(arr, n, m, i, j + 1, (status | leftk(j)) ^ leftk(j), dp);
a.p2 = -1;
if (a.left == 0 && a.up == 0 && a.cur == 0 && a.right == 0)
int32 next2 = process2(arr, n, m, i, j + 1, status | leftk(j), dp);
if (next2 != -1)
a.p2 = 1 + next2;
a.ans = max(a.p1, a.p2);
dp[uint32(i)][uint32(j)][uint32(status)] = a.ans;
return a.ans;
function status0(int32 status, int32 i, int32 m)public pure returns (int32)
return (i < 0 || i == m || (status & (leftk(i))) == 0) ? int32(0) : int32(1);
function leftk(int32 k) public pure returns (int32)
int32 ans = 1;
while (k>0)
ans*=2;
k--;
return ans;
function max(int32 a,int32 b)public pure returns (int32)
if(a>b)
return a;
else
return b;
// 局部变量超过了16个,需要用结构体封装
struct A
int32 left;
int32 up;
int32 cur;
int32 right;
int32 p1;
int32 p2;
int32 ans;
代码用rust编写。代码如下:
use rand::Rng;
use std::iter::repeat;
fn main()
let mut matrix = vec![vec![0, 0], vec![0, 0]];
let ans3 = most_seats2(&mut matrix);
println!("ans3 = ", ans3);
let nn: i32 = 10;
let mm: i32 = 10;
let one_p = 15;
let test_time: i32 = 10000;
println!("测试开始");
for i in 0..test_time
let n = rand::thread_rng().gen_range(0, nn) + 1;
let m = rand::thread_rng().gen_range(0, mm) + 1;
let mut matrix = random_matrix(n, m, one_p);
let ans1 = most_seats1(&mut matrix);
let ans2 = most_seats2(&mut matrix);
if ans1 != ans2
println!("出错了!", i);
println!("ans1 = ", ans1);
println!("ans2 = ", ans2);
break;
println!("测试结束");
// 为了测试,普通方法
// 普通的状态压缩动态规划
// 每一行用dfs的方法
// 体系学习班,章节44 : 状态压缩的动态规划,贴瓷砖问题类似
fn most_seats1(map: &mut Vec<Vec<i32>>) -> i32
let n = map.len() as i32;
let m = map[0].len() as i32;
let mut arr: Vec<i32> = repeat(0).take(n as usize).collect();
for row in 0..n
let mut status = 0;
let mut col = 0;
let mut i = m - 1;
while col < m
if map[row as usize][col as usize] == 1
if row > 0 && map[(row - 1) as usize][col as usize] == 1
return -1;
if col > 0 && map[row as usize][(col - 1) as usize] == 1
return -1;
status |= map[row as usize][col as usize] << i;
col += 1;
i -= 1;
arr[row as usize] = status;
let mut dp: Vec<Vec<i32>> = repeat(repeat(-2).take((1 << m) as usize).collect())
.take(n as usize)
.collect();
let ans = process1(&mut arr, 0, 0, m, &mut dp);
return if ans == -1 0 else ans ;
fn process1(arr: &mut Vec<i32>, row: i32, pre: i32, m: i32, dp: &mut Vec<Vec<i32>>) -> i32
if row == arr.len() as i32
return 0;
if dp[row as usize][pre as usize] != -2
return dp[row as usize][pre as usize];
let cur = arr[row as usize];
let mut ans = 0;
if (cur & pre) != 0
ans = -1;
else
ans = dfs(arr, row, m - 1, pre, cur, m, dp);
dp[row as usize][pre as usize] = ans;
return ans;
fn dfs(
arr: &mut Vec<i32>,
row: i32,
col: i32,
pre: i32,
seats: i32,
m: i32,
dp: &mut Vec<Vec<i32>>,
) -> i32
if col == -1
return process1(arr, row + 1, seats, m, dp);
else
let p1 = dfs(arr, row, col - 1, pre, seats, m, dp);
let mut p2 = -1;
if (pre & (1 << col)) == 0
&& (seats & (1 << col)) == 0
&& (col == m - 1 || (seats & (1 << (col + 1))) == 0)
&& (col == 0 || (seats & (1 << (col - 1))) == 0)
let next2 = dfs(arr, row, col - 1, pre, seats | (1 << col), m, dp以上是关于2023-01-14:给定一个二维数组map,代表一个餐厅,其中只有01两种值 map[i][j] == 0 表示(i,j)位置是空座 map[i][j] == 1 表示(i,j)位置坐了人 根据防的主要内容,如果未能解决你的问题,请参考以下文章
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