default value = value;
default flip = flip;

nbr target;

if(flip == 0) {
  value = no:value;
}
else {
  if(flip == '<') {
    target: = we:; 

    if(value != 0 && target:value != 0)
      if(target:value > value)
        value = target:value;
   
    flip = '>';
  }
  else {
    target: = ea:;
   
    if(value != 0 && target:value != 0)
      if(target:value < value)
        value = target:value;
  
    flip = '<';
  }
}