diff --git a/README.md b/README.md
index f93b6ba..c450077 100644
--- a/README.md
+++ b/README.md
@@ -1,2 +1,4 @@
 # JavaLocalBase
  Simple local base for java problems
+
+https://leetcode.com/explore/challenge/card/july-leetcoding-challenge-2021/608/week-1-july-1st-july-7th/3803/
\ No newline at end of file
diff --git a/src/main/java/Main.java b/src/main/java/Main.java
index d08a4f0..f3ebd2c 100644
--- a/src/main/java/Main.java
+++ b/src/main/java/Main.java
@@ -1,46 +1,158 @@
-import java.io.FileInputStream;
-import java.io.FileNotFoundException;
-import java.io.FileOutputStream;
-import java.io.IOException;
+import java.util.*;
 
 public class Main {
-    public static void main(String[] args) throws IOException {
+    public static void main(String[] args)  {
         CodeWorker code = new CodeWorker();
-        code.fileInputReadStream();
-        System.out.println(code.testMethod());
     }
 
 
 }
 
 class CodeWorker {
-    public void fileInputReadStream() throws IOException {
-        FileInputStream in = null;
-        FileOutputStream out = null;
 
-        try {
-            in = new FileInputStream("src/input.txt");
-            out = new FileOutputStream("output.txt");
+    private Integer startTime;
+    private Integer endTime;
+    private Integer meetingMinutes;
 
-            int c;
-            while ((c = in.read()) != -1) {
-                out.write(c);
+    public String testMethod() {
+        return "method";
+    }
+
+    public List<String> getPossibleScheduleTimes(List<List<String>> schedules, List<String> bounds, String meetingLength) {
+        var complementaryTimeBlocks = new ArrayList<String>();
+
+        var schedule1 = schedules.get(0);
+        var schedule2 = schedules.get(1);
+
+        var schedule1Free = new ArrayList<TimeRange>();
+        var schedule2Free = new ArrayList<TimeRange>();
+
+        var originalStartTime = this.translateToMinutes(bounds.get(0));
+        this.startTime = this.translateToMinutes(bounds.get(0));
+        this.endTime = this.translateToMinutes(bounds.get(1));
+        this.meetingMinutes = this.translateToMinutes(meetingLength);
+
+        if (schedule1.size() > schedule2.size()) {
+            // traverse the smaller schedule first
+            var temp = schedule2;
+            schedule2 = schedule1;
+            schedule1 = temp;
+        }
+
+        for (var i = 0; i < schedule1.size(); i++) {
+            var time = schedule1.get(i);
+            var timeRange = this.parseTimeRange(time);
+            var lastTimeBlockerToThisMeeting = (timeRange.startTime - startTime);
+            var hasFreeSpace = lastTimeBlockerToThisMeeting >= meetingMinutes;
+
+            if (hasFreeSpace) {
+                schedule1Free.add(new TimeRange(startTime, timeRange.startTime));
             }
-        } catch (FileNotFoundException e) {
-            e.printStackTrace();
-        } catch (IOException e) {
-            e.printStackTrace();
-        } finally {
-            if (in != null) {
-                in.close();
+            startTime = timeRange.endTime;
+
+            if (i == schedule1.size()-1) {
+                if((endTime - timeRange.endTime) >= meetingMinutes ) {
+                    schedule1Free.add(new TimeRange(timeRange.endTime, endTime));
+                }
             }
-            if (out != null) {
-                out.close();
+        }
+
+        startTime = originalStartTime;
+
+        for (var i = 0; i < schedule2.size(); i++) {
+            var time = schedule2.get(i);
+            var timeRange = this.parseTimeRange(time);
+            var lastTimeBlockerToThisMeeting = (timeRange.startTime - startTime);
+            var hasFreeSpace = lastTimeBlockerToThisMeeting >= meetingMinutes;
+
+            if (hasFreeSpace) {
+                schedule2Free.add(new TimeRange(startTime, timeRange.startTime));
+            }
+            startTime = timeRange.endTime;
+
+            if (i == schedule2.size()-1) {
+                if((endTime - timeRange.endTime) >= meetingMinutes ) {
+                    schedule2Free.add(new TimeRange(timeRange.endTime, endTime));
+                }
             }
         }
+
+        var schedule2Pointer= 0;
+        for (var free1: schedule1Free) {
+            for (var i=schedule2Pointer; i < schedule2Free.size(); i++) {
+                var free2 = schedule2Free.get(i);
+                var isFree2WraparoundFree1 = free1.startTime >= free2.startTime && free1.endTime <= free2.endTime;
+                var isFree2InnerBlockOfFree1 = free1.startTime <= free2.startTime && free1.endTime >= free2.endTime;
+                var isFree2AtStartOfFree1 = free1.startTime >= free2.startTime && free2.endTime <= free1.endTime;
+                var isFree2AtTheEndOfFree1 = free1.startTime <= free2.startTime && free2.endTime >= free1.endTime;
+
+                if (isFree2WraparoundFree1) {
+                    complementaryTimeBlocks.add(free1.toTimeString());
+                    schedule2Pointer = i;
+                } else if (isFree2InnerBlockOfFree1) {
+                    if ((free2.endTime - free2.startTime) >=meetingMinutes) {
+                        complementaryTimeBlocks.add(free2.toTimeString());
+                    } else {
+                        schedule2Pointer = i;
+                    }
+                } else if (isFree2AtStartOfFree1) {
+                    if ((free2.endTime - free1.startTime) >= meetingMinutes) {
+                        complementaryTimeBlocks.add(new TimeRange(free1.startTime, free2.endTime).toTimeString());
+                    } else {
+                        schedule2Pointer = i;
+                    }
+                } else if (isFree2AtTheEndOfFree1) {
+                    if ((free1.endTime - free2.startTime) >= meetingMinutes) {
+                        complementaryTimeBlocks.add(new TimeRange(free2.startTime, free1.endTime).toTimeString());
+                    } else {
+                        schedule2Pointer = i;
+                        break;
+                    }
+                } else {
+                    schedule2Pointer = i;
+                    break;
+                }
+            }
+        }
+
+        return complementaryTimeBlocks;
     }
 
-    public String testMethod() {
-        return "method";
+    private TimeRange parseTimeRange(String time) {
+        var rangeSplit = time.split("-");
+        var startTime = this.translateToMinutes(rangeSplit[0]);
+        var endTime = this.translateToMinutes(rangeSplit[1]);
+        return new TimeRange(startTime, endTime);
+    }
+
+    private Integer translateToMinutes(String time) {
+        var hoursAndMinutes = time.split(":");
+        var hours = Integer.parseInt(hoursAndMinutes[0]);
+        var minutes = Integer.parseInt(hoursAndMinutes[1]);
+
+        return hours*60 + minutes;
+    }
+}
+
+class TimeRange {
+    public Integer startTime;
+    public Integer endTime;
+
+    public TimeRange(Integer s, Integer e) {
+        this.startTime = s;
+        this.endTime = e;
+    }
+
+    public String toTimeString() {
+        return this.timeIntegerToMilitaryTime(this.startTime) + "-"+ this.timeIntegerToMilitaryTime(this.endTime);
+    }
+
+    private String timeIntegerToMilitaryTime(Integer time) {
+        var hours = time / 60;
+        var minutes = time % 60;
+
+        var hourString = hours == 0 ? "00" : hours + "";
+        var minuteString = minutes == 0 ? "00": minutes + "";
+        return hourString+":"+minuteString;
     }
 }
diff --git a/src/test/java/MainTest.java b/src/test/java/MainTest.java
index 679e36c..2510929 100644
--- a/src/test/java/MainTest.java
+++ b/src/test/java/MainTest.java
@@ -1,6 +1,10 @@
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 
+import java.lang.reflect.Array;
+import java.util.Arrays;
+import java.util.List;
+
 import static org.junit.jupiter.api.Assertions.*;
 
 class MainTest {
@@ -16,4 +20,27 @@ public void setUp() throws Exception{
     void testMethod() {
         assertEquals(codeWorker.testMethod(), "method");
     }
+
+
+    @Test
+    void test() {
+        List<String> schedule1 = Arrays.asList("10:00-11:30", "15:10-16:20");
+        List<String> schedule2 = Arrays.asList("8:00-9:30", "12:00-16:00", "17:20-18:00");
+        List<List<String>> schedules = Arrays.asList(schedule1, schedule2);
+        List<String> bounds = Arrays.asList("8:00","18:00");
+        String meetingLength = "0:45";
+
+        assertEquals(Arrays.asList("16:20-17:20"),codeWorker.getPossibleScheduleTimes(schedules, bounds, meetingLength));
+    }
+
+    @Test
+    void test2() {
+        List<String> schedule1 = Arrays.asList("10:15-11:30", "15:10-16:20");
+        List<String> schedule2 = Arrays.asList("8:45-9:30", "12:00-16:00", "17:10-17:15");
+        List<List<String>> schedules = Arrays.asList(schedule1, schedule2);
+        List<String> bounds = Arrays.asList("8:00","18:00");
+        String meetingLength = "0:45";
+
+        assertEquals(Arrays.asList("8:00-8:45","9:30-10:15","16:20-17:10","17:15-18:00"),codeWorker.getPossibleScheduleTimes(schedules, bounds, meetingLength));
+    }
 }
\ No newline at end of file
diff --git a/target/classes/Main.class b/target/classes/Main.class
index 1a32117..3dd50d2 100644
Binary files a/target/classes/Main.class and b/target/classes/Main.class differ
diff --git a/target/test-classes/MainTest.class b/target/test-classes/MainTest.class
index 9fa99ed..349b0ca 100644
Binary files a/target/test-classes/MainTest.class and b/target/test-classes/MainTest.class differ