title: Using " contains " in kotlin for provide if the input have contains english letters
body: <p>how can I use &quot; contains &quot;?
  if the input have contains english letters it's always shows me false even if am write a english letter small/capital</p>
  <pre><code> val eLang: String = (&quot;aA b   B c   C d   D e   E f   F g   G h   H i   I j   J k   K l   L m   M n   N o   O p   P q   Q r   R s   S t   T u   U v   V w   W x   X y   Y z   Z&quot;)
  
  
     
  </code></pre>
  <p>output : false</p>
  <pre><code>       println( input_string?.contains(eLang, ignoreCase = true))
  </code></pre>
  <p>main code</p>
  <pre><code>class Loop {
  
      public val input_string: String? = readLine().toString()
      public val input_size = readLine()?.toInt()
  
      fun looping(a: String, b: Int) {
          val eLang: String = (&quot;aA b   B c   C d   D e   E f   F g   G h   H i   I j   J k   K l   L m   M n   N o   O p   P q   Q r   R s   S t   T u   U v   V w   W x   X y   Y z   Z&quot;)
          if ((input_size!! &gt; 1) &amp;&amp; input_string != &quot;&quot;) {
              for (i in 0 until input_size) {
  
                  println(input_string)
              }
  
              input_string?.let { println(&quot;length word you type : ${it.length}&quot;) }
              input_size?.let { println(&quot;Count looping: ${(input_size)}&quot;) }
  
             println( input_string?.contains(eLang, ignoreCase = true))
  
  
  
          }
      }
  
  }
  </code></pre>