adding old solved challenges

BinarySearch/BinarySearch.java

@@ -0,0 +1,42 @@
+import java.util.Arrays;
+
+public class BinarySearch {
+  public static void main(String[] args) {
+    int[] seriesofNumbers = { 12, 14, 16, 17, 85, 5, 42, 23, 54, 96, 56, 45, 43, 32, 99, 33, 6, 77, 66, 98, 56, 43, 21,
+        22 };
+
+    System.err.println(BinarySearchDo(seriesofNumbers, 33));
+  }
+
+  public static int BinarySearchDo(int[] sortedNumbers, int wantedNumber) {
+    // let's set the first and last indecies of the array
+    int left = 0;
+    int right = sortedNumbers.length - 1;
+    // we sort the array just in case it is a series of random numbers
+    Arrays.sort(sortedNumbers);
+    for (int sortedNum : sortedNumbers) {
+      System.out.print(sortedNum + " ");
+    }
+    System.out.println("");
+    // let's split the array into 2 and compare if the middle number is lower or
+    // larger than the wanted number
+    while (left <= right) {
+      int middleIndex = (left + right) / 2;
+      int middleNumber = sortedNumbers[middleIndex];
+      System.out.println("The last index of this Array is " + right + " and the Middile index is " + middleIndex
+          + " ==> " + middleNumber);
+      System.out.println("");
+      if (wantedNumber == middleNumber) {
+        System.out.println("");
+        return middleIndex;
+      }
+      if (wantedNumber < middleNumber) {
+        right = middleIndex - 1;
+      }
+      if (wantedNumber > middleNumber) {
+        left = middleIndex + 1;
+      }
+    }
+    return -1;
+  }
+}