Segments covering by points

Author: ProgrammingLanguageLeader

src/algorithms/segments_covering_by_points/Main.java

@@ -0,0 +1,46 @@
+package algorithms.segments_covering_by_points;
+
+import java.util.Arrays;
+import java.util.Scanner;
+import java.util.Vector;
+
+public class Main {
+    private void run() {
+        Scanner scanner = new Scanner(System.in);
+        int segmentsCount = scanner.nextInt();
+        Segment[] segments = new Segment[segmentsCount];
+        for (int i = 0; i < segmentsCount; i++) {
+            int left = scanner.nextInt();
+            int right = scanner.nextInt();
+            segments[i] = new Segment(left, right);
+        }
+
+        Arrays.sort(segments);
+        Vector<Integer> usedPoints = new Vector<>();
+        for (int i = 0; i < segments.length; i++)  {
+            if (segments[i].isMarked()) {
+                continue;
+            }
+            usedPoints.add(segments[i].getRight());
+            segments[i].setMarked(true);
+            for (int j = i + 1; j < segments.length; j++) {
+                if (segments[j].getLeft() <= usedPoints.lastElement()) {
+                    segments[j].setMarked(true);
+                } else {
+                    break;
+                }
+            }
+        }
+
+        StringBuilder outputBuilder = new StringBuilder();
+        outputBuilder.append(String.format("%d\n", usedPoints.size()));
+        for (int point : usedPoints) {
+            outputBuilder.append(String.format("%d ", point));
+        }
+        System.out.println(outputBuilder.toString());
+    }
+
+    public static void main(String[] args) {
+        new Main().run();
+    }
+}

src/algorithms/segments_covering_by_points/Segment.java

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+package algorithms.segments_covering_by_points;
+
+public class Segment implements Comparable<Segment>
+{
+    private Integer left;
+    private Integer right;
+    private boolean marked;
+
+    Segment(int left, int right) {
+        this.left = left;
+        this.right = right;
+        marked = false;
+    }
+
+    @Override
+    public int compareTo(Segment o) {
+        return this.right.compareTo(o.right);
+    }
+
+    public Integer getRight() {
+        return right;
+    }
+
+    public void setRight(Integer right) {
+        this.right = right;
+    }
+
+    public Integer getLeft() {
+        return left;
+    }
+
+    public void setLeft(Integer left) {
+        this.left = left;
+    }
+
+    public boolean isMarked() {
+        return marked;
+    }
+
+    public void setMarked(boolean marked) {
+        this.marked = marked;
+    }
+};