Scala Procedure Stuck in Infinite Loop ( I think )

The following code is a manual version of an array sorting algorithm, taking any array of integers, and changing that array so that it is in non-decreasing order. For some reason, my scala console just sits there (seemingly computing things) when I call this procedure on an array, and I don't know why.

def main(a: Array[Int]) {
    var l = a.length
    var switchesLeft = true

    while( switchesLeft == true) {

      var z = 0
      var i = 0;

      while( i < l ) {
        开发者_如何学Govar x = i + 1

        if( x == l ) x = 0

        if( a(i) > a(x) ) {
          // Switch the elements
          var t = a(x)
          a(x) = a(i)
          a(i) = t

          z += 1;
        }

        i += 1
      }

      if( z == 0) {
        // No switches were done
        switchesLeft = false
      }

    }
}

The reason for cycling is if( x == l ) x = 0. Leave it out, and write while( i + 1 < l ) for the loop condition, then it works.

Here is a slightly improved version:

def sort(a: Array[Int]) {
  var l = a.length
  var switchesLeft = true

  while(switchesLeft) {

    switchesLeft = false
    for(i <- 0 until l-1 if a(i) > a(i+1)){
      // Switch the elements
      val t = a(i+1)
      a(i+1) = a(i)
      a(i) = t

      switchesLeft = true
    }
  }
}