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lab3.md

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+# Lab Report 3
+
+## Part 1
+
+### Associated Code
+
+```java
+// Changes the input array to be in reversed order
+static void reverseInPlace(int[] arr) {
+    for(int i = 0; i < arr.length; i += 1) {
+        arr[i] = arr[arr.length - i - 1];
+    }
+}
+```
+
+Failure-inducing Input (Test)
+
+```java
+@Test
+public void testReverseInPlace() {
+    int[] input1 = {1, 2, 3, 4, 5, 6};
+    ArrayExamples.reverseInPlace(input1);
+    assertArrayEquals(new int[]{6, 5, 4, 3, 2, 1}, input1);
+}
+```
+
+Non Failure-inducing Input
+
+```java
+@Test
+public void testReverseOneElementInPlace() {
+    int[] input1 = {1};
+    ArrayExamples.reverseInPlace(input1);
+    assertArrayEquals(new int[]{1}, input1);
+}
+```
+
+### Symptoms
+
+```
+JUnit version 4.13.2
+..E
+Time: 0.044
+There was 1 failure:
+1) testReverseInPlace(ArrayTests)
+arrays first differed at element [3]; expected:<3> but was:<4>
+        at org.junit.internal.ComparisonCriteria.arrayEquals(ComparisonCriteria.java:78)
+        at org.junit.internal.ComparisonCriteria.arrayEquals(ComparisonCriteria.java:28)
+        at org.junit.Assert.internalArrayEquals(Assert.java:534)
+        at org.junit.Assert.assertArrayEquals(Assert.java:418)
+        at org.junit.Assert.assertArrayEquals(Assert.java:429)
+        at ArrayTests.testReverseInPlace(ArrayTests.java:11)
+        ... 32 trimmed
+Caused by: java.lang.AssertionError: expected:<3> but was:<4>
+        at org.junit.Assert.fail(Assert.java:89)
+        at org.junit.Assert.failNotEquals(Assert.java:835)
+        at org.junit.Assert.assertEquals(Assert.java:120)
+        at org.junit.Assert.assertEquals(Assert.java:146)
+        at org.junit.internal.ExactComparisonCriteria.assertElementsEqual(ExactComparisonCriteria.java:8)
+        at org.junit.internal.ComparisonCriteria.arrayEquals(ComparisonCriteria.java:76)
+        ... 38 more
+
+FAILURES!!!
+Tests run: 2,  Failures: 1
+```
+
+### Fix the Bug
+
+#### Before:
+
+```java
+static void reverseInPlace(int[] arr) {
+    for(int i = 0; i < arr.length; i += 1) {
+        arr[i] = arr[arr.length - i - 1];
+    }
+}
+```
+
+#### After:
+
+```java
+static void reverseInPlace(int[] arr) {
+    for (int i = 0; i < arr.length / 2; i += 1) {
+        int temp = arr[i];
+        arr[i] = arr[arr.length - i - 1];
+        arr[arr.length - i - 1] = temp;
+    }
+}
+```
+
+> The fix addresses the issue because the value is updated without storing the previous value. Before the temp variable is added and the loop is loop only for half of the array, the `arr[i] = arr[arr.length - i - 1];` directly override the value that we need to save it and interchange it. By loop through only half of the array and switch the elements between each other with the value stored in the `temp` first address the problem that the method change the array value with the wrong way.
+
+## Part 2