#Modification 53

amangit1314 · amangit1314 · commit 3ec49132279a · 2021-08-04T13:21:02.000+05:30
diff --git a/sortingAlgorithms/InsertionSort.java b/sortingAlgorithms/InsertionSort.java
@@ -0,0 +1,41 @@
+package sortingAlgorithms;
+
+public class InsertionSort {
+
+    /*Function to sort array using insertion sort*/
+    void sort(int arr[])
+    {
+        int n = arr.length;
+        for (int i = 1; i < n; ++i) {
+            int key = arr[i];
+            int j = i - 1;
+
+            while (j >= 0 && arr[j] > key) {
+                arr[j + 1] = arr[j];
+                j = j - 1;
+            }
+            arr[j + 1] = key;
+        }
+    }
+
+    /* A utility function to print array of size n*/
+    static void printArray(int arr[])
+    {
+        int n = arr.length;
+        for (int i = 0; i < n; ++i)
+            System.out.print(arr[i] + " ");
+
+        System.out.println();
+    }
+
+    // Driver method
+    public static void main(String args[])
+    {
+        int arr[] = { 12, 11, 13, 5, 6 };
+
+        InsertionSort ob = new InsertionSort();
+        ob.sort(arr);
+
+        printArray(arr);
+    }
+}
diff --git a/sortingAlgorithms/MergeSort.java b/sortingAlgorithms/MergeSort.java
@@ -0,0 +1,96 @@
+package sortingAlgorithms;
+
+public class MergeSort {
+    // Merges two subarrays of arr[].
+    // First subarray is arr[l..m]
+    // Second subarray is arr[m+1..r]
+    void merge(int arr[], int l, int m, int r) {
+        // Find sizes of two subarrays to be merged
+        int n1 = m - l + 1;
+        int n2 = r - m;
+
+        /* Create temp arrays */
+        int L[] = new int[n1];
+        int R[] = new int[n2];
+
+        /*Copy data to temp arrays*/
+        for (int i = 0; i < n1; ++i)
+            L[i] = arr[l + i];
+        for (int j = 0; j < n2; ++j)
+            R[j] = arr[m + 1 + j];
+
+        /* Merge the temp arrays */
+
+        // Initial indexes of first and second subarrays
+        int i = 0, j = 0;
+
+        // Initial index of merged subarry array
+        int k = l;
+        while (i < n1 && j < n2) {
+            if (L[i] <= R[j]) {
+                arr[k] = L[i];
+                i++;
+            }
+            else {
+                arr[k] = R[j];
+                j++;
+            }
+            k++;
+        }
+
+        /* Copy remaining elements of L[] if any */
+        while (i < n1) {
+            arr[k] = L[i];
+            i++;
+            k++;
+        }
+
+        /* Copy remaining elements of R[] if any */
+        while (j < n2) {
+            arr[k] = R[j];
+            j++;
+            k++;
+        }
+    }
+
+    // Main function that sorts arr[l..r] using
+    // merge()
+    void sort(int arr[], int l, int r)
+    {
+        if (l < r) {
+            // Find the middle point
+            int m =l+ (r-l)/2;
+
+            // Sort first and second halves
+            sort(arr, l, m);
+            sort(arr, m + 1, r);
+
+            // Merge the sorted halves
+            merge(arr, l, m, r);
+        }
+    }
+
+    /* A utility function to print array of size n */
+    static void printArray(int arr[])
+    {
+        int n = arr.length;
+        for (int i = 0; i < n; ++i)
+            System.out.print(arr[i] + " ");
+        System.out.println();
+    }
+
+    // Driver code
+    public static void main(String args[])
+    {
+        int arr[] = { 12, 11, 13, 5, 6, 7 };
+
+        System.out.println("Given Array");
+        printArray(arr);
+
+        MergeSort ob = new MergeSort();
+        ob.sort(arr, 0, arr.length - 1);
+
+        System.out.println("\nSorted array");
+        printArray(arr);
+    }
+}
diff --git a/sortingAlgorithms/QuickSort.java b/sortingAlgorithms/QuickSort.java
@@ -0,0 +1,91 @@
+package sortingAlgorithms;
+
+import java.io.*;
+
+public class QuickSort{
+
+    // A utility function to swap two elements
+    static void swap(int[] arr, int i, int j)
+    {
+        int temp = arr[i];
+        arr[i] = arr[j];
+        arr[j] = temp;
+    }
+
+    /* This function takes last element as pivot, places
+       the pivot element at its correct position in sorted
+       array, and places all smaller (smaller than pivot)
+       to left of pivot and all greater elements to right
+       of pivot */
+    static int partition(int[] arr, int low, int high)
+    {
+
+        // pivot
+        int pivot = arr[high];
+
+        // Index of smaller element and
+        // indicates the right position
+        // of pivot found so far
+        int i = (low - 1);
+
+        for(int j = low; j <= high - 1; j++)
+        {
+
+            // If current element is smaller
+            // than the pivot
+            if (arr[j] < pivot)
+            {
+
+                // Increment index of
+                // smaller element
+                i++;
+                swap(arr, i, j);
+            }
+        }
+        swap(arr, i + 1, high);
+        return (i + 1);
+    }
+
+    /* The main function that implements QuickSort
+              arr[] --> Array to be sorted,
+              low --> Starting index,
+              high --> Ending index
+     */
+    static void quickSort(int[] arr, int low, int high)
+    {
+        if (low < high)
+        {
+
+            // pi is partitioning index, arr[p]
+            // is now at right place
+            int pi = partition(arr, low, high);
+
+            // Separately sort elements before
+            // partition and after partition
+            quickSort(arr, low, pi - 1);
+            quickSort(arr, pi + 1, high);
+        }
+    }
+
+    // Function to print an array
+    static void printArray(int[] arr, int size)
+    {
+        for(int i = 0; i < size; i++)
+            System.out.print(arr[i] + " ");
+
+        System.out.println();
+    }
+
+    // Driver Code
+    public static void main(String[] args)
+    {
+        int[] arr = { 10, 7, 8, 9, 1, 5 };
+        int n = arr.length;
+
+        quickSort(arr, 0, n - 1);
+        System.out.println("Sorted array: ");
+        printArray(arr, n);
+    }
+}
+
+// This code is contributed by Aman Soni
diff --git a/sortingAlgorithms/SelectionSort.java b/sortingAlgorithms/SelectionSort.java
@@ -0,0 +1,41 @@
+package sortingAlgorithms;
+
+public class SelectionSort {
+
+    void sort(int arr[])
+    {
+        int n = arr.length;
+
+        // One by one move boundary of unsorted sub-array
+        for (int i = 0; i < n-1; i++) {
+            // Find the minimum element in unsorted array
+            int min_idx = i;
+            for (int j = i+1; j < n; j++)
+                if (arr[j] < arr[min_idx])
+                    min_idx = j;
+
+            // Swap the found minimum element with the first
+            // element
+            int temp = arr[min_idx];
+            arr[min_idx] = arr[i];
+            arr[i] = temp;
+        }
+    }
+
+    // Prints the array
+    void printArray(int arr[]) {
+        int n = arr.length;
+        for (int i=0; i<n; ++i)
+            System.out.print(arr[i]+" ");
+        System.out.println();
+    }
+
+    // Driver code to test above
+    public void main(String args[]){
+        SelectionSort ob = new SelectionSort();
+        int arr[] = {5,11,13,6,12};
+        ob.sort(arr);
+        System.out.println("Sorted array");
+        ob.printArray(arr);
+    }
+}
