val N:ℕ;
val M:ℕ;
axiom notZero ⇔ N > 0;

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

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

proc maximumIndex(a:array):int
{
  var m:elem ≔ 0;
  var p:int ≔ -1;
  for var i:int ≔ 0; i < N; i ≔ i+1 do
  {
    if a[i] > m then p ≔ i;
  }
  return p;
}

proc main(): ()
{
  // execution for N=5 and M=3
  val a = Array[N,elem](1,2,3,0,1);
  // print a, maximumElement(a);
  // print a, maximumIndex(a);
}