val N:ℕ;
val M:ℕ; 

type int   = ℤ[-1,N];
type elem  = ℤ[-1,M];
type array = Array[N,elem];

proc maximumElement(a:array,n:int): elem
{
  var m:elem ≔ 0;
  var i:int ≔ 0;
  while i < n do
  {
    if a[i] > m then m ≔ a[i]; 
    i ≔ i+1;
  }
  return m;
}