.

README.md

@@ -9,6 +9,18 @@ Create a function that receives an integers array and returns the number that ap
 | (1,1,2)         | 2        |
 | (2,2,1)         | 1        |
 
+fun OnlyOnce(var numbers: Array<Int>):Int{
+    foreach (i in numbers.size){
+      var x : Int
+      if (i == x){
+      //do nothing its existed
+      }
+    else{
+    return i
+    } 
+      x = i
+    }
+}
 
 ## 2nd Challenge
 Create a function that receives a string then it converts uppercase letters into lowercase and vice versa. The function then should print the converted value.
@@ -21,6 +33,14 @@ Create a function that receives a string then it converts uppercase letters into
 | My name is Ali | mY NAME IS aLI |
 | sHroog         | ShROOG         |
 
+fun Strings.toLowercase (val h :String ){
+ this.super()
+ if(h.char){}
+}
+
+
+
+
 
 ## 3rd Challenge
 Create a function that receives an array of items & arrays and returns one flattened array with all items exluding null values.
@@ -33,6 +53,10 @@ Create a function that receives an array of items & arrays and returns one flatt
 | 4 | [3, 5, [5, 9, 0]]                     | [3, 5, 5, 9, 0]       |
 
 
+fun (array:Array<Int>):Array<Int>{
+return array.filter(Number)
+}
+
 ## 4th Challenge
 Create a function that receives a string that contains combination of parentheses, square brackets, and curly braces. Then, it returns true if every opening bracket has a closing pair.
 
@@ -49,5 +73,11 @@ Create a function that receives a string that contains combination of parenthese
 | {[(}])   | true     |
 | {[}])    | false    |
 
-
+fun g (var g : String):Boolean{
+if (g.count > 1){
+return false
+}
+elseif(){
+} 
+}