upadting the file

binary_search.java

@@ -1,40 +1,40 @@
-public class BinarySearch {
-    public static int binarySearch(int[] arr, int target) {
-        int left = 0;
-        int right = arr.length - 1;
-
-        while (left <= right) {
-            int mid = left + (right - left) / 2;
-
-            // If the target is found at the middle index, return it.
-            if (arr[mid] == target) {
-                return mid;
-            }
-
-            // If the target is smaller, search the left half.
-            if (arr[mid] > target) {
-                right = mid - 1;
-            }
-            // If the target is larger, search the right half.
-            else {
-                left = mid + 1;
-            }
-        }
+public class Main{
 
-        // If the target element is not found, return -1.
-        return -1;
-    }
+    public static int binarySearch(int array[], int left, int right, int item){
+
+        if (right >= left){
 
-    public static void main(String[] args) {
-        int[] sortedArray = {1, 3, 5, 7, 9, 11, 13, 15};
-        int targetElement = 7;
+            // calculation of new mid
+            int mid = left + (right - left)/2;
 
-        int result = binarySearch(sortedArray, targetElement);
+            // returns position where found
+            if (array[mid] == item)
+                return mid+1;
 
-        if (result != -1) {
-            System.out.println("Element " + targetElement + " found at index " + result + ".");
-        } else {
-            System.out.println("Element " + targetElement + " not found in the array.");
+            // goes to recursive calls in left half
+            if (array[mid] > item)
+                return binarySearch(array, left, mid-1, item);
+
+                // goes to recursive calls in right half
+            else
+                return binarySearch(array, mid+1, right, item);
         }
+        // if element is not found we return -1
+        else
+            return -1;
+    }
+    public static void main(String args[]){
+
+        int[ ] array = {10, 20, 30, 40, 50, 60, 70, 80};
+        int item = 70;
+        int size = array.length;
+
+        int position = binarySearch(array, 0, size-1, item);
+
+        if(position == -1)
+            System.out.println("Element not found");
+        else
+            System.out.println("The value " + item + " found at position: " + position);
+
     }
 }

calculator.java

@@ -1,56 +1,61 @@
+// Java program for simple calculator
+import java.io.*;
+import java.lang.*;
+import java.lang.Math;
 import java.util.Scanner;
 
-class Main {
-  public static void main(String[] args) {
-
-    char operator;
-    Double number1, number2, result;
-
-    // create an object of Scanner class
-    Scanner input = new Scanner(System.in);
-
-    // ask users to enter operator
-    System.out.println("Choose an operator: +, -, *, or /");
-    operator = input.next().charAt(0);
-
-    // ask users to enter numbers
-    System.out.println("Enter first number");
-    number1 = input.nextDouble();
-
-    System.out.println("Enter second number");
-    number2 = input.nextDouble();
-
-    switch (operator) {
-
-      // performs addition between numbers
-      case '+':
-        result = number1 + number2;
-        System.out.println(number1 + " + " + number2 + " = " + result);
-        break;
-
-      // performs subtraction between numbers
-      case '-':
-        result = number1 - number2;
-        System.out.println(number1 + " - " + number2 + " = " + result);
-        break;
-
-      // performs multiplication between numbers
-      case '*':
-        result = number1 * number2;
-        System.out.println(number1 + " * " + number2 + " = " + result);
-        break;
-
-      // performs division between numbers
-      case '/':
-        result = number1 / number2;
-        System.out.println(number1 + " / " + number2 + " = " + result);
-        break;
-
-      default:
-        System.out.println("Invalid operator!");
-        break;
-    }
-
-    input.close();
-  }
-}
+// Driver class
+public class BasicCalculator {
+	// main function
+	public static void main(String[] args)
+	{
+		// Stores two numbers
+		double num1, num2;
+
+		// Take input from the user
+		Scanner sc = new Scanner(System.in);
+
+		System.out.println("Enter the numbers:");
+
+		// Take the inputs
+		num1 = sc.nextDouble();
+		num2 = sc.nextDouble();
+
+		System.out.println("Enter the operator (+,-,*,/):");
+
+		char op = sc.next().charAt(0);
+		double o = 0;
+
+		switch (op) {
+		// case to add two numbers
+		case '+':
+			o = num1 + num2;
+			break;
+
+		// case to subtract two numbers
+		case '-':
+			o = num1 - num2;
+			break;
+
+		// case to multiply two numbers
+		case '*':
+			o = num1 * num2;
+			break;
+
+		// case to divide two numbers
+		case '/':
+			o = num1 / num2;
+			break;
+
+		default:
+			System.out.println("You enter wrong input");
+		}
+
+		System.out.println("The final result:");
+		System.out.println();
+
+		// print the final result
+		System.out.println(num1 + " " + op + " " + num2
+						+ " = " + o);
+	}
+}