Merge branch 'master' into neha-practice

Author: neha-peddinti

src/com/codefortomorrow/advanced/chapter13/examples/BinarySearch.java

@@ -0,0 +1,43 @@
+package com.codefortomorrow.advanced.chapter13.examples;
+
+public class BinarySearch {
+
+    // Java implementation of recursive Binary Search
+    // Returns index of x if it is present in arr[l..
+    // r], else return -1
+    public static int binarySearch(int arr[], int l, int r, int x) {
+        if (r >= l) {
+            int mid = l + (r - l) / 2;
+
+            // If the element is present at the
+            // middle itself
+            if (arr[mid] == x) return mid;
+
+            // If element is smaller than mid, then
+            // it can only be present in left subarray
+            if (arr[mid] > x) return binarySearch(arr, l, mid - 1, x);
+
+            // Else the element can only be present
+            // in right subarray
+            return binarySearch(arr, mid + 1, r, x);
+        }
+
+        // We reach here when element is not present
+        // in array
+        return -1;
+    }
+
+    // Driver method to test above
+    public static void main(String args[]) {
+        int arr[] = { 2, 3, 4, 10, 40 };
+        int n = arr.length;
+        int x = 10;
+        int result = binarySearch(arr, 0, n - 1, x);
+        if (result == -1) System.out.println(
+            "Element not present"
+        ); else System.out.println("Element found at index " + result);
+    }
+    /* This code is contributed by Rajat Mishra
+    https://www.geeksforgeeks.org/binary-search/ */
+
+}

src/com/codefortomorrow/advanced/chapter13/examples/Fibonacci.java

@@ -0,0 +1,29 @@
+package com.codefortomorrow.advanced.chapter13.examples;
+
+public class Fibonacci {
+
+    public static int fibonacciRecursion(int nthNumber) {
+        //use recursion
+        if (nthNumber == 0) {
+            return 0;
+        } else if (nthNumber == 1) {
+            return 1;
+        }
+        return (
+            fibonacciRecursion(nthNumber - 1) +
+            fibonacciRecursion(nthNumber - 2)
+        );
+    }
+
+    public static int fibonacciLoop(int nthNumber) {
+        //use loop
+        int previouspreviousNumber, previousNumber = 0, currentNumber = 1;
+        for (int i = 1; i < nthNumber; i++) {
+            previouspreviousNumber = previousNumber;
+            previousNumber = currentNumber;
+            currentNumber = previouspreviousNumber + previousNumber;
+        }
+        return currentNumber;
+    }
+    // Credit: https://dev.to/khalilsaboor/fibonacci-recursion-vs-iteration--474l
+}

src/com/codefortomorrow/advanced/chapter13/practice/RecurMergeSort.java

@@ -0,0 +1,6 @@
+package com.codefortomorrow.advanced.chapter13.practice;
+
+public class RecurMergeSort {
+
+    public static void recurMergeSort(Comparable[] array, int start, int end) {}
+}

src/com/codefortomorrow/advanced/chapter13/solutions/RecurMergeSort.java

@@ -0,0 +1,42 @@
+package com.codefortomorrow.advanced.chapter13.solutions;
+
+public class RecurMergeSort {
+
+    public static void recurMergeSort(Comparable[] array, int start, int end) {
+        if (start >= end) {
+            return;
+        }
+        int middle = (start + end) / 2;
+        recurMergeSort(array, start, middle);
+        recurMergeSort(array, middle + 1, end);
+        int i = start;
+        int j = middle + 1;
+        Comparable[] sortedArray = new Comparable[end - start + 1];
+        int k = 0;
+        while (i <= middle && j <= end) {
+            if (array[i].compareTo(array[j]) > 0) {
+                sortedArray[k] = array[i];
+                i++;
+            } else {
+                sortedArray[k] = array[j];
+                j++;
+            }
+            k++;
+        }
+        while (i <= middle) {
+            sortedArray[k] = array[i];
+            i++;
+            k++;
+        }
+        while (j <= end) {
+            sortedArray[k] = array[j];
+            j++;
+            k++;
+        }
+        k = 0;
+        for (int l = start; l <= end; l++) {
+            array[l] = sortedArray[k];
+            k++;
+        }
+    }
+}

src/com/codefortomorrow/advanced/chapter14/examples/BufferedReaderExample.java

@@ -0,0 +1,41 @@
+package com.codefortomorrow.advanced.chapter14.examples;
+
+import java.io.BufferedReader;
+import java.io.FileReader;
+import java.io.IOException;
+
+/**
+ * Source: https://beginnersbook.com/2014/01/how-to-read-file-in-java-using-bufferedreader/
+ */
+public class BufferedReaderExample {
+
+    public static void main(String[] args) {
+        BufferedReader br = null;
+        BufferedReader br2 = null;
+
+        try {
+            br = new BufferedReader(new FileReader("B:\\myfile.txt"));
+
+            //One way of reading the file
+            System.out.println("Reading the file using readLine() method:");
+            String contentLine = br.readLine();
+            while (contentLine != null) {
+                System.out.println(contentLine);
+                contentLine = br.readLine();
+            }
+
+            br2 = new BufferedReader(new FileReader("B:\\myfile2.txt"));
+
+            //Second way of reading the file
+            System.out.println("Reading the file using read() method:");
+            int num = 0;
+            char ch;
+            while ((num = br2.read()) != -1) {
+                ch = (char) num;
+                System.out.print(ch);
+            }
+        } catch (IOException ioe) {
+            ioe.printStackTrace();
+        }
+    }
+}

src/com/codefortomorrow/advanced/chapter14/examples/FileIO.java

@@ -1,4 +1,5 @@
-package com.codefortomorrow.advanced.chapter14.examples
+package com.codefortomorrow.advanced.chapter14.examples;
+
 import java.io.*;
 
 public class FileIO {
@@ -7,22 +8,20 @@ public static void main(String[] args) throws IOException {
         FileInputStream in = null;
         FileOutputStream out = null;
         File file = new File("names.txt");
-        
+
         try {
             in = new FileInputStream(file);
             out = new FileOutputStream("names_upper.txt");
             int c;
-            while ((c = in.read()) != -1)
-                out.write(Character.toUpperCase((char)c));
-
+            while ((c = in.read()) != -1) out.write(
+                Character.toUpperCase((char) c)
+            );
         } catch (IOException e) {
             System.out.println("An IO Exception occurred.");
-            e.printStackTrace();  // Prints error output stream.
+            e.printStackTrace(); // Prints error output stream.
         } finally {
-            if (in != null)
-                in.close();
-            if (out != null)
-                out.close();
+            if (in != null) in.close();
+            if (out != null) out.close();
         }
     }
 }

src/com/codefortomorrow/advanced/chapter14/examples/TryWithResources.java

@@ -1,21 +1,23 @@
-package com.codefortomorrow.advanced.chapter14.examples
+package com.codefortomorrow.advanced.chapter14.examples;
+
 import java.io.*;
 
 public class TryWithResources {
 
     public static void main(String[] args) throws IOException {
         File file = new File("names.txt");
-        
-        try (FileInputStream in = new FileInputStream(file);
-            FileOutputStream out = new FileOutputStream("names_upper.txt")) {
 
+        try (
+            FileInputStream in = new FileInputStream(file);
+            FileOutputStream out = new FileOutputStream("names_upper.txt")
+        ) {
             int c;
-            while ((c = in.read()) != -1)
-                out.write(Character.toUpperCase((char)c));
-
+            while ((c = in.read()) != -1) out.write(
+                Character.toUpperCase((char) c)
+            );
         } catch (IOException e) {
             System.out.println("An IO Exception occurred.");
-            e.printStackTrace();  // Prints error output stream.
+            e.printStackTrace(); // Prints error output stream.
         }
     }
 }

src/com/codefortomorrow/advanced/chapter14/practice/Average.java

@@ -1,4 +1,5 @@
 package com.codefortomorrow.advanced.chapter14.practice;
+
 import java.io.*;
 
 /*
@@ -24,8 +25,8 @@ and display the average on the next (101st)
 */
 
 public class Average {
-    public static void main(String[] args) {
 
+    public static void main(String[] args) {
         // Add code here.
     }
 }

src/com/codefortomorrow/advanced/chapter14/practice/Bank.java

@@ -27,11 +27,9 @@ balance upon initialization (through the constructor).
 */
 
 public class Bank {
-    
-    public static void main(String[] args) {
 
+    public static void main(String[] args) {
         // Your code here.
     }
 }
-
 // Add other classes here.

src/com/codefortomorrow/advanced/chapter14/practice/Lexico.java

@@ -0,0 +1,21 @@
+package com.codefortomorrow.advanced.chapter14.practice;
+
+import java.io.*;
+
+/*
+Practice: Use File I/O to compare two files lexicographically.
+Lexicographical order is very similar to alphabetical order,
+except that it includes more than just lowercase alphabets.
+Given two text files f1 and f2, write a program that will
+compare their contents and output to the console the
+title of the file which comes first lexicographically.
+
+Hint: Java’s String.compareTo method may be of use to you.
+*/
+
+public class Lexico {
+
+    public static void main(String[] args) {
+        // Add code here
+    }
+}