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feat: add solutions to lc problems: No.0296,2448
* No.0296.Best Meeting Point * No.2448.Minimum Cost to Make Array Equal
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‎solution/0200-0299/0296.Best Meeting Point/README.md

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@@ -46,22 +46,143 @@
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<!-- 这里可写通用的实现逻辑 -->
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**方法一：排序 + 中位数**
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对于每一行，我们可以将所有的 $1$ 的下标排序，然后取中位数 $i$ 作为碰头地点的横坐标。
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对于每一列，我们可以将所有的 $1$ 的下标排序，然后取中位数 $i$ 作为碰头地点的纵坐标。
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最后，我们计算所有 $1$ 到碰头地点 $(i, j)$ 的曼哈顿距离之和即可。
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时间复杂度 $O(m\times n\times \log(m\times n))$。最多有 $m\times n$ 个 $1$，排序的时间复杂度为 $\log(m\times n)$。
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相似题目：
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- [462. 最少移动次数使数组元素相等 II](/solution/0400-0499/0462.Minimum%20Moves%20to%20Equal%20Array%20Elements%20II/README.md)
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- [2448. 使数组相等的最小开销](/solution/2400-2499/2448.Minimum%20Cost%20to%20Make%20Array%20Equal/README.md)
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<!-- tabs:start -->
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### **Python3**
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<!-- 这里可写当前语言的特殊实现逻辑 -->
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```python
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class Solution:
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def minTotalDistance(self, grid: List[List[int]]) -> int:
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def f(arr, x):
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return sum(abs(v - x) for v in arr)
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rows, cols = [], []
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for i, row in enumerate(grid):
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for j, v in enumerate(row):
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if v:
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rows.append(i)
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cols.append(j)
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cols.sort()
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i = rows[len(rows) >> 1]
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j = cols[len(cols) >> 1]
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return f(rows, i) + f(cols, j)
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```
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### **Java**
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<!-- 这里可写当前语言的特殊实现逻辑 -->
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```java
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class Solution {
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public int minTotalDistance(int[][] grid) {
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int m = grid.length, n = grid[0].length;
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List<Integer> rows = new ArrayList<>();
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List<Integer> cols = new ArrayList<>();
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for (int i = 0; i < m; ++i) {
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for (int j = 0; j < n; ++j) {
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if (grid[i][j] == 1) {
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rows.add(i);
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cols.add(j);
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}
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}
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}
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Collections.sort(cols);
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int i = rows.get(rows.size() >> 1);
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int j = cols.get(cols.size() >> 1);
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return f(rows, i) + f(cols, j);
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}
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private int f(List<Integer> arr, int x) {
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int s = 0;
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for (int v : arr) {
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s += Math.abs(v - x);
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}
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return s;
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}
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}
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```
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### **C++**
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```cpp
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class Solution {
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public:
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int minTotalDistance(vector<vector<int>>& grid) {
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int m = grid.size(), n = grid[0].size();
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vector<int> rows;
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vector<int> cols;
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for (int i = 0; i < m; ++i) {
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for (int j = 0; j < n; ++j) {
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if (grid[i][j]) {
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rows.emplace_back(i);
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cols.emplace_back(j);
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}
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}
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}
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sort(cols.begin(), cols.end());
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int i = rows[rows.size() / 2];
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int j = cols[cols.size() / 2];
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auto f = [](vector<int>& arr, int x) {
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int s = 0;
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for (int v : arr) {
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s += abs(v - x);
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}
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return s;
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};
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return f(rows, i) + f(cols, j);
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}
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};
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```
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### **Go**
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```go
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func minTotalDistance(grid [][]int) int {
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rows, cols := []int{}, []int{}
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for i, row := range grid {
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for j, v := range row {
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if v == 1 {
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rows = append(rows, i)
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cols = append(cols, j)
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}
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}
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}
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sort.Ints(cols)
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i := rows[len(rows)>>1]
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j := cols[len(cols)>>1]
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f := func(arr []int, x int) int {
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s := 0
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for _, v := range arr {
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s += abs(v - x)
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}
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return s
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}
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return f(rows, i) + f(cols, j)
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}
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func abs(x int) int {
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if x < 0 {
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return -x
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}
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return x
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}
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```
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### **...**

‎solution/0200-0299/0296.Best Meeting Point/README_EN.md

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@@ -46,13 +46,119 @@ So return 6.
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### **Python3**
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```python
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class Solution:
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def minTotalDistance(self, grid: List[List[int]]) -> int:
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def f(arr, x):
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return sum(abs(v - x) for v in arr)
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rows, cols = [], []
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for i, row in enumerate(grid):
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for j, v in enumerate(row):
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if v:
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rows.append(i)
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cols.append(j)
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cols.sort()
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i = rows[len(rows) >> 1]
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j = cols[len(cols) >> 1]
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return f(rows, i) + f(cols, j)
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```
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### **Java**
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```java
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class Solution {
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public int minTotalDistance(int[][] grid) {
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int m = grid.length, n = grid[0].length;
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List<Integer> rows = new ArrayList<>();
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List<Integer> cols = new ArrayList<>();
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for (int i = 0; i < m; ++i) {
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for (int j = 0; j < n; ++j) {
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if (grid[i][j] == 1) {
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rows.add(i);
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cols.add(j);
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}
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}
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}
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Collections.sort(cols);
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int i = rows.get(rows.size() >> 1);
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int j = cols.get(cols.size() >> 1);
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return f(rows, i) + f(cols, j);
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}
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private int f(List<Integer> arr, int x) {
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int s = 0;
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for (int v : arr) {
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s += Math.abs(v - x);
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}
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return s;
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}
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}
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```
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### **C++**
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```cpp
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class Solution {
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public:
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int minTotalDistance(vector<vector<int>>& grid) {
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int m = grid.size(), n = grid[0].size();
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vector<int> rows;
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vector<int> cols;
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for (int i = 0; i < m; ++i) {
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for (int j = 0; j < n; ++j) {
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if (grid[i][j]) {
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rows.emplace_back(i);
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cols.emplace_back(j);
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}
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}
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}
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sort(cols.begin(), cols.end());
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int i = rows[rows.size() / 2];
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int j = cols[cols.size() / 2];
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auto f = [](vector<int>& arr, int x) {
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int s = 0;
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for (int v : arr) {
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s += abs(v - x);
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}
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return s;
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};
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return f(rows, i) + f(cols, j);
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}
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};
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```
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### **Go**
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```go
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func minTotalDistance(grid [][]int) int {
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rows, cols := []int{}, []int{}
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for i, row := range grid {
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for j, v := range row {
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if v == 1 {
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rows = append(rows, i)
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cols = append(cols, j)
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}
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}
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}
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sort.Ints(cols)
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i := rows[len(rows)>>1]
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j := cols[len(cols)>>1]
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f := func(arr []int, x int) int {
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s := 0
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for _, v := range arr {
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s += abs(v - x)
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}
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return s
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}
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return f(rows, i) + f(cols, j)
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}
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func abs(x int) int {
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if x < 0 {
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return -x
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}
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return x
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}
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```
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### **...**

‎solution/0200-0299/0296.Best Meeting Point/Solution.cpp

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class Solution {
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public:
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int minTotalDistance(vector<vector<int>>& grid) {
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int m = grid.size(), n = grid[0].size();
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vector<int> rows;
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vector<int> cols;
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for (int i = 0; i < m; ++i) {
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for (int j = 0; j < n; ++j) {
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if (grid[i][j]) {
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rows.emplace_back(i);
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cols.emplace_back(j);
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}
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}
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}
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sort(cols.begin(), cols.end());
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int i = rows[rows.size() / 2];
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int j = cols[cols.size() / 2];
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auto f = [](vector<int>& arr, int x) {
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int s = 0;
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for (int v : arr) {
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s += abs(v - x);
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}
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return s;
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};
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return f(rows, i) + f(cols, j);
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}
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};

‎solution/0200-0299/0296.Best Meeting Point/Solution.go

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func minTotalDistance(grid [][]int) int {
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rows, cols := []int{}, []int{}
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for i, row := range grid {
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for j, v := range row {
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if v == 1 {
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rows = append(rows, i)
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cols = append(cols, j)
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}
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}
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}
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sort.Ints(cols)
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i := rows[len(rows)>>1]
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j := cols[len(cols)>>1]
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f := func(arr []int, x int) int {
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s := 0
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for _, v := range arr {
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s += abs(v - x)
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}
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return s
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}
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return f(rows, i) + f(cols, j)
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}
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func abs(x int) int {
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if x < 0 {
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return -x
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}
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return x
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}

‎solution/0200-0299/0296.Best Meeting Point/Solution.java

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class Solution {
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public int minTotalDistance(int[][] grid) {
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int m = grid.length, n = grid[0].length;
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List<Integer> rows = new ArrayList<>();
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List<Integer> cols = new ArrayList<>();
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for (int i = 0; i < m; ++i) {
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for (int j = 0; j < n; ++j) {
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if (grid[i][j] == 1) {
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rows.add(i);
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cols.add(j);
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}
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}
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}
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Collections.sort(cols);
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int i = rows.get(rows.size() >> 1);
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int j = cols.get(cols.size() >> 1);
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return f(rows, i) + f(cols, j);
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}
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private int f(List<Integer> arr, int x) {
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int s = 0;
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for (int v : arr) {
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s += Math.abs(v - x);
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}
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return s;
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}
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}

‎solution/0200-0299/0296.Best Meeting Point/Solution.py

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class Solution:
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def minTotalDistance(self, grid: List[List[int]]) -> int:
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def f(arr, x):
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return sum(abs(v - x) for v in arr)
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rows, cols = [], []
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for i, row in enumerate(grid):
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for j, v in enumerate(row):
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if v:
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rows.append(i)
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cols.append(j)
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cols.sort()
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i = rows[len(rows) >> 1]
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j = cols[len(cols) >> 1]
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return f(rows, i) + f(cols, j)

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