Help with syntax of code--can't figure out problem

[SIZE=1]Flash is telling me that there are 2 syntax errors in my code–I can’t figure it out. I have put the text in red that Flash is telling me is wrong. If someone could help me figure it out…

displayTime = 20;

function countDown() {
[COLOR=Red] displayTime–;
if (displayTime <= 0) {[/COLOR]
var n:Number = (Math.floor(Math.random()*5)+1);
var blnOK:Boolean = false;

if (n == 5) {
       if (_root.Singleton.sContainer7 == "shakespearBust_11") { 
    blnOK = true;
    }
  } else if (n == 3) {
       if (_root.Singleton.sContainer7 == "lavaLamp_7") {
    blnOK = true;
       }
  } else {
       blnOK = true;
      }
 }
 
 if (blnOK) {
       displayTime = 20;
       trace("Times Up");
       trace(_root.Singleton.sContainer7); 
       trace(_root.Singleton.sContainer11);
       container21_mc.loadMovie("objects/random"+n+"_21/random"+n+"_21.swf", "_root.movieclip"); 
  }

timer = setInterval(countDown, 1000);
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