Day 34, Java

.all-contributorsrc

@@ -328,6 +328,16 @@
         "doc",
         "code"
       ]
+    },
+    {
+      "login": "ldrf",
+      "name": "ldrf",
+      "avatar_url": "https://avatars0.githubusercontent.com/u/38339210?v=4",
+      "profile": "https://github.com/ldrf",
+      "contributions": [
+        "doc",
+        "code"
+      ]
     }
   ],
   "commitConvention": "none"

CONTRIBUTORS.md

@@ -49,6 +49,7 @@ Thanks goes to these wonderful people ([emoji key](https://github.com/kentcdodds
     <td align="center"><a href="https://github.com/gaurav01k3"><img src="https://avatars0.githubusercontent.com/u/67451786?v=4?s=100" width="100px;" alt=""/><br /><sub><b>GAURAV KUMAR</b></sub></a><br /><a href="https://github.com/CodeToExpress/dailycodebase/commits?author=gaurav01k3" title="Documentation">📖</a> <a href="https://github.com/CodeToExpress/dailycodebase/commits?author=gaurav01k3" title="Code">💻</a></td>
     <td align="center"><a href="https://github.com/wboccard"><img src="https://avatars3.githubusercontent.com/u/72316984?v=4?s=100" width="100px;" alt=""/><br /><sub><b>wboccard</b></sub></a><br /><a href="https://github.com/CodeToExpress/dailycodebase/commits?author=wboccard" title="Documentation">📖</a> <a href="https://github.com/CodeToExpress/dailycodebase/commits?author=wboccard" title="Code">💻</a></td>
     <td align="center"><a href="https://github.com/d-l-mcbride"><img src="https://avatars3.githubusercontent.com/u/46550732?v=4?s=100" width="100px;" alt=""/><br /><sub><b>d-l-mcbride</b></sub></a><br /><a href="https://github.com/CodeToExpress/dailycodebase/commits?author=d-l-mcbride" title="Documentation">📖</a> <a href="https://github.com/CodeToExpress/dailycodebase/commits?author=d-l-mcbride" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/ldrf"><img src="https://avatars0.githubusercontent.com/u/38339210?v=4?s=100" width="100px;" alt=""/><br /><sub><b>ldrf</b></sub></a><br /><a href="https://github.com/CodeToExpress/dailycodebase/commits?author=ldrf" title="Documentation">📖</a> <a href="https://github.com/CodeToExpress/dailycodebase/commits?author=ldrf" title="Code">💻</a></td>
   </tr>
 </table>
 

day34/Java/MergeSort.java

@@ -0,0 +1,80 @@
+/**
+ * @author Lucas Freire(ldrf)
+ * @date 16/10/2020
+ */
+
+import java.util.Arrays;
+
+public class MergeSort {
+
+	public static void main(String[] args) {
+		int[] arrayToOrder = new int[]{1, 5, 2, 7, 3, 4, 8, 9, 6};
+		System.out.println("Array before sorting");
+		System.out.println(Arrays.toString(arrayToOrder));
+		int startIndex = 0;
+		int highIdex = arrayToOrder.length - 1;
+		mergeSort(arrayToOrder, startIndex, highIdex);
+		System.out.println("Array after sorting");
+		System.out.println(Arrays.toString(arrayToOrder));
+	}
+
+	private static void mergeSort(int[] arrayToOrder, int lowIndex,
+			int highIndex) {
+		if (lowIndex < highIndex) {
+			int firstMidIndex = (lowIndex + highIndex) / 2;
+			mergeSort(arrayToOrder, lowIndex, firstMidIndex);
+			int secondMidIndex = firstMidIndex + 1;
+			mergeSort(arrayToOrder, secondMidIndex, highIndex);
+			merge(arrayToOrder, lowIndex, firstMidIndex, highIndex);
+		}
+	}
+
+	private static void merge(int[] arrayToOrder, int lowIndex, int midIndex,
+			int highIndex) {
+		int leftSubArraySize = (midIndex - lowIndex) + 1;
+		int rightSubArraySize = highIndex - midIndex;
+		int[] leftArray = getArray(arrayToOrder, leftSubArraySize, lowIndex);
+		int[] rightArray = getArray(arrayToOrder, rightSubArraySize,
+				midIndex + 1);
+		int leftCounter = 0;
+		int rightCounter = 0;
+		while ((leftCounter < leftSubArraySize)
+				&& (rightCounter < rightSubArraySize)) {
+			if (leftArray[leftCounter] <= rightArray[rightCounter]) {
+				arrayToOrder[lowIndex] = leftArray[leftCounter];
+				++leftCounter;
+			} else {
+				arrayToOrder[lowIndex] = rightArray[rightCounter];
+				++rightCounter;
+			}
+			++lowIndex;
+
+		}
+
+		lowIndex = remainingElements(arrayToOrder, lowIndex, leftSubArraySize,
+				leftArray, leftCounter);
+		remainingElements(arrayToOrder, lowIndex, rightSubArraySize, rightArray,
+				rightCounter);
+
+	}
+
+	private static int[] getArray(int[] arrayToOrder, int arraySideSize,
+			int startIndex) {
+		int[] sideArray = new int[arraySideSize];
+		for (int i = 0; i < sideArray.length; i++) {
+			sideArray[i] = arrayToOrder[startIndex + i];
+		}
+		return sideArray;
+	}
+
+	private static int remainingElements(int[] arrayToOrder, int startIndex,
+			int subArraySizeSide, int[] sideArray, int sideCounter) {
+		while (sideCounter < subArraySizeSide) {
+			arrayToOrder[startIndex] = sideArray[sideCounter];
+			++startIndex;
+			++sideCounter;
+		}
+		return startIndex;
+	}
+
+}

day34/README.md

@@ -125,3 +125,88 @@ int main(){
     return 0;
 }
 ```
+
+### [Java Implementation](./Java/MergeSort.Java)
+``` java
+/**
+ * @author Lucas Freire(ldrf)
+ * @date 16/10/2020
+ */
+
+import java.util.Arrays;
+
+public class MergeSort {
+
+	public static void main(String[] args) {
+		int[] arrayToOrder = new int[]{1, 5, 2, 7, 3, 4, 8, 9, 6};
+		System.out.println("Array before sorting");
+		System.out.println(Arrays.toString(arrayToOrder));
+		int startIndex = 0;
+		int highIdex = arrayToOrder.length - 1;
+		mergeSort(arrayToOrder, startIndex, highIdex);
+		System.out.println("Array after sorting");
+		System.out.println(Arrays.toString(arrayToOrder));
+	}
+
+	private static void mergeSort(int[] arrayToOrder, int lowIndex,
+			int highIndex) {
+		if (lowIndex < highIndex) {
+			int firstMidIndex = (lowIndex + highIndex) / 2;
+			mergeSort(arrayToOrder, lowIndex, firstMidIndex);
+			int secondMidIndex = firstMidIndex + 1;
+			mergeSort(arrayToOrder, secondMidIndex, highIndex);
+			merge(arrayToOrder, lowIndex, firstMidIndex, highIndex);
+		}
+	}
+
+	private static void merge(int[] arrayToOrder, int lowIndex, int midIndex,
+			int highIndex) {
+		int leftSubArraySize = (midIndex - lowIndex) + 1;
+		int rightSubArraySize = highIndex - midIndex;
+		int[] leftArray = getArray(arrayToOrder, leftSubArraySize, lowIndex);
+		int[] rightArray = getArray(arrayToOrder, rightSubArraySize,
+				midIndex + 1);
+		int leftCounter = 0;
+		int rightCounter = 0;
+		while ((leftCounter < leftSubArraySize)
+				&& (rightCounter < rightSubArraySize)) {
+			if (leftArray[leftCounter] <= rightArray[rightCounter]) {
+				arrayToOrder[lowIndex] = leftArray[leftCounter];
+				++leftCounter;
+			} else {
+				arrayToOrder[lowIndex] = rightArray[rightCounter];
+				++rightCounter;
+			}
+			++lowIndex;
+
+		}
+
+		lowIndex = remainingElements(arrayToOrder, lowIndex, leftSubArraySize,
+				leftArray, leftCounter);
+		remainingElements(arrayToOrder, lowIndex, rightSubArraySize, rightArray,
+				rightCounter);
+
+	}
+
+	private static int[] getArray(int[] arrayToOrder, int arraySideSize,
+			int startIndex) {
+		int[] sideArray = new int[arraySideSize];
+		for (int i = 0; i < sideArray.length; i++) {
+			sideArray[i] = arrayToOrder[startIndex + i];
+		}
+		return sideArray;
+	}
+
+	private static int remainingElements(int[] arrayToOrder, int startIndex,
+			int subArraySizeSide, int[] sideArray, int sideCounter) {
+		while (sideCounter < subArraySizeSide) {
+			arrayToOrder[startIndex] = sideArray[sideCounter];
+			++startIndex;
+			++sideCounter;
+		}
+		return startIndex;
+	}
+
+}
+
+```