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Commit d1c9ae8

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feat: add solutions to lc problems: No.3111,3112 (doocs#2583)
* No.3111.Minimum Rectangles to Cover Points * No.3112.Minimum Time to Visit Disappearing Nodes
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-18
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13 files changed

+683
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‎solution/3100-3199/3111.Minimum Rectangles to Cover Points/README.md‎

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## 解法
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### 方法一
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### 方法一:贪心 + 排序
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根据题目描述,我们不需要考虑矩形的高度,只需要考虑矩形的宽度。
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我们可以将所有的点按照横坐标进行排序,用一个变量 $x_1$ 记录当前矩形的左下角的横坐标。然后遍历所有的点,如果当前点的横坐标 $x$ 比 $x_1 + w$ 大,说明当前点不能被当前的矩形覆盖,我们就需要增加一个新的矩形,然后更新 $x_1$ 为当前点的横坐标。
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遍历完成后,我们就得到了最少需要多少个矩形。
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时间复杂度 $O(n \times \log n),ドル空间复杂度 $O(\log n)$。其中 $n$ 是点的数量。
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<!-- tabs:start -->
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```python
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class Solution:
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def minRectanglesToCoverPoints(self, points: List[List[int]], w: int) -> int:
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points.sort()
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ans, x1 = 0, -inf
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for x, _ in points:
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if x1 + w < x:
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x1 = x
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ans += 1
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return ans
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```
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```java
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class Solution {
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public int minRectanglesToCoverPoints(int[][] points, int w) {
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Arrays.sort(points, (a, b) -> a[0] - b[0]);
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int ans = 0;
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int x1 = -(1 << 30);
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for (int[] p : points) {
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int x = p[0];
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if (x1 + w < x) {
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x1 = x;
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++ans;
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}
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}
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return ans;
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}
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}
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```
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```cpp
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class Solution {
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public:
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int minRectanglesToCoverPoints(vector<vector<int>>& points, int w) {
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sort(points.begin(), points.end());
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int ans = 0, x1 = -(1 << 30);
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for (auto& p : points) {
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int x = p[0];
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if (x1 + w < x) {
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x1 = x;
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++ans;
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}
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}
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return ans;
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}
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};
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```
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```go
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func minRectanglesToCoverPoints(points [][]int, w int) (ans int) {
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sort.Slice(points, func(i, j int) bool { return points[i][0] < points[j][0] })
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x1 := -(1 << 30)
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for _, p := range points {
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if x := p[0]; x1+w < x {
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x1 = x
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ans++
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}
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}
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return
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}
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```
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```ts
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function minRectanglesToCoverPoints(points: number[][], w: number): number {
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points.sort((a, b) => a[0] - b[0]);
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let ans = 0;
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let x1 = -Infinity;
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for (const [x, _] of points) {
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if (x1 + w < x) {
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x1 = x;
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++ans;
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}
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}
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return ans;
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}
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```
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<!-- tabs:end -->

‎solution/3100-3199/3111.Minimum Rectangles to Cover Points/README_EN.md‎

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## Solutions
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### Solution 1
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### Solution 1: Greedy + Sorting
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According to the problem description, we don't need to consider the height of the rectangle, only the width.
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We can sort all the points according to the x-coordinate and use a variable $x_1$ to record the current x-coordinate of the lower left corner of the rectangle. Then we traverse all the points. If the x-coordinate $x$ of the current point is greater than $x_1 + w,ドル it means that the current point cannot be covered by the current rectangle. We need to add a new rectangle and update $x_1$ to the x-coordinate of the current point.
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After the traversal, we get the minimum number of rectangles needed.
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The time complexity is $O(n \times \log n),ドル and the space complexity is $O(\log n),ドル where $n$ is the number of points.
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<!-- tabs:start -->
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```python
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class Solution:
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def minRectanglesToCoverPoints(self, points: List[List[int]], w: int) -> int:
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points.sort()
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ans, x1 = 0, -inf
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for x, _ in points:
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if x1 + w < x:
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x1 = x
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ans += 1
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return ans
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```
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```java
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class Solution {
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public int minRectanglesToCoverPoints(int[][] points, int w) {
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Arrays.sort(points, (a, b) -> a[0] - b[0]);
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int ans = 0;
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int x1 = -(1 << 30);
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for (int[] p : points) {
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int x = p[0];
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if (x1 + w < x) {
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x1 = x;
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++ans;
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}
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}
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return ans;
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}
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}
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```
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```cpp
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class Solution {
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public:
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int minRectanglesToCoverPoints(vector<vector<int>>& points, int w) {
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sort(points.begin(), points.end());
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int ans = 0, x1 = -(1 << 30);
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for (auto& p : points) {
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int x = p[0];
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if (x1 + w < x) {
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x1 = x;
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++ans;
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}
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}
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return ans;
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}
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};
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```
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```go
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func minRectanglesToCoverPoints(points [][]int, w int) (ans int) {
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sort.Slice(points, func(i, j int) bool { return points[i][0] < points[j][0] })
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x1 := -(1 << 30)
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for _, p := range points {
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if x := p[0]; x1+w < x {
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x1 = x
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ans++
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}
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}
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return
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}
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```
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```ts
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function minRectanglesToCoverPoints(points: number[][], w: number): number {
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points.sort((a, b) => a[0] - b[0]);
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let ans = 0;
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let x1 = -Infinity;
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for (const [x, _] of points) {
217+
if (x1 + w < x) {
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x1 = x;
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++ans;
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}
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}
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return ans;
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}
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```
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<!-- tabs:end -->
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@@ -0,0 +1,15 @@
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class Solution {
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public:
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int minRectanglesToCoverPoints(vector<vector<int>>& points, int w) {
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sort(points.begin(), points.end());
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int ans = 0, x1 = -(1 << 30);
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for (auto& p : points) {
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int x = p[0];
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if (x1 + w < x) {
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x1 = x;
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++ans;
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}
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}
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return ans;
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}
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};
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func minRectanglesToCoverPoints(points [][]int, w int) (ans int) {
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sort.Slice(points, func(i, j int) bool { return points[i][0] < points[j][0] })
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x1 := -(1 << 30)
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for _, p := range points {
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if x := p[0]; x1+w < x {
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x1 = x
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ans++
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}
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}
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return
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}
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Original file line numberDiff line numberDiff line change
@@ -0,0 +1,15 @@
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class Solution {
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public int minRectanglesToCoverPoints(int[][] points, int w) {
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Arrays.sort(points, (a, b) -> a[0] - b[0]);
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int ans = 0;
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int x1 = -(1 << 30);
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for (int[] p : points) {
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int x = p[0];
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if (x1 + w < x) {
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x1 = x;
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++ans;
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}
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}
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return ans;
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}
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}
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Original file line numberDiff line numberDiff line change
@@ -0,0 +1,9 @@
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class Solution:
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def minRectanglesToCoverPoints(self, points: List[List[int]], w: int) -> int:
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points.sort()
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ans, x1 = 0, -inf
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for x, _ in points:
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if x1 + w < x:
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x1 = x
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ans += 1
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return ans
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function minRectanglesToCoverPoints(points: number[][], w: number): number {
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points.sort((a, b) => a[0] - b[0]);
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let ans = 0;
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let x1 = -Infinity;
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for (const [x, _] of points) {
6+
if (x1 + w < x) {
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x1 = x;
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++ans;
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}
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}
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return ans;
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}

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