nextcommit

Author: shashankch

src/revision/MergeOverlapInterval.java

@@ -1,7 +1,85 @@
 package revision;
 
+import java.util.Arrays;
+import java.util.Comparator;
+import java.util.Stack;
+
+class Interval {
+
+    int start;
+    int end;
+
+    Interval(int start, int end) {
+
+        this.start = start;
+        this.end = end;
+    }
+
+}
+
+
 public class MergeOverlapInterval {
 
-    
-    
-}
+
+    public static void mergeinterval(Interval arr[]) {
+
+        if (arr.length <= 0) {
+            return;
+        }
+
+        Arrays.sort(arr, new Comparator<Interval>() {
+
+            public int compare(Interval a, Interval b) {
+
+                return a.start - b.start;
+                // here -1,0,1 represent asc,equal,desc..
+            }
+        });
+
+        Stack<Interval> stk = new Stack<>();
+
+        stk.push(arr[0]);
+
+        for (int i = 1; i < arr.length; i++) {
+
+            Interval top = stk.peek();
+
+            if (top.end < arr[i].start) {
+
+                stk.push(arr[i]);
+            } else if (top.end < arr[i].end) {
+
+                top.end = arr[i].end;
+                stk.pop();
+                stk.push(top);
+
+
+            }
+
+
+
+        }
+
+        while (!stk.isEmpty()) {
+            Interval ans = stk.pop();
+            System.out.println(ans.start + " " + ans.end);
+        }
+
+
+
+    }
+
+
+
+    public static void main(String[] args) {
+
+        int n = 4;
+        Interval arr[] = new Interval[n];
+        arr[0] = new Interval(6, 8);
+        mergeinterval(arr);
+
+    }
+
+
+
+}