Add Binary Search in Kotlin (#4510)

Author: Bolshialex

archive/k/kotlin/BinarySearch.kt

@@ -0,0 +1,56 @@
+fun main(args : Array<String>){
+    if (args.size != 2) {
+        println("Usage: please provide a list of sorted integers (\"1, 4, 5, 11, 12\") and the integer to find (\"11\")")
+        return
+    }
+
+    val listInput = args[0].replace(",", "")
+    val targetInput = args[1]
+
+    val arr: IntArray
+    val target: Int
+
+    try {
+        arr = listInput.split(" ").map { it.toInt() }.toIntArray()
+        target = targetInput.toInt()
+    } catch (e: NumberFormatException) {
+        println("Usage: please provide a list of sorted integers (\"1, 4, 5, 11, 12\") and the integer to find (\"11\")")
+        return
+    }
+
+    if (!isSorted(arr)) {
+        println("Usage: please provide a list of sorted integers (\"1, 4, 5, 11, 12\") and the integer to find (\"11\")")
+        return
+    }
+
+    val result = binarySearch(arr, target)
+    println(result)
+}
+
+fun binarySearch(arr: IntArray, target: Int): Boolean{
+    var left = 0;
+    var right = arr.size - 1
+
+    while(left <= right){
+        var mid = (left + right) / 2;
+        if(arr[mid] == target){
+            return true
+        } else if(arr[mid] < target){
+            left = mid + 1
+        }else{
+            right = mid - 1
+        }
+    }
+        
+    return false
+}
+
+
+fun isSorted(arr: IntArray): Boolean {
+    for (i in 0 until arr.size - 1) {
+        if (arr[i] > arr[i + 1]) {
+            return false
+        }
+    }
+    return true
+}