function add (x : integer; y : integer) return integer is
begin
	return x + y;
end;

function add2 (x : integer; y : integer) return integer is
begin
	return add(x, y) + add(x, y);
end;


function even (x: integer)  return integer is
	begin
               if  (x / 2) * 2 = x then
                 return 1;
               
               else 
                 return 0;
               end if; 
      end;


function slow_pow (base : integer; exponent : integer) return integer is
              result : integer;
   begin
               result := 1;

               for j in 1 ..  exponent loop
                  result := result * base;
               end;

               return result;
   end;


function fib (n : integer) return integer is
	type table is array of integer;
	values : table [10];
 begin
              values [0] := 1;
              values [1] := 1;

              for j in 2 .. n loop
                 values [j] := values [j - 1] + values [j - 2];
              end;

              return values [n];
end;


function fib2 (a : integer; n : integer) return integer is

 begin
              a [0] := 1;
              a [1] := 1;

              for j in 2 .. n loop
                 a [j] := a [j - 1] + a [j - 2];
              end;

              return a [n];
end;


function recurse (x : integer) return integer is
begin
	if x = 0 then
		return 0;
	else
		return recurse (x - 1) + x;
	end if;
end;



function pow (base: integer; exponent : integer) return integer is
               temp : integer;
     begin
               if exponent = 0 then
               		return 1;
               end if;

		if exponent = 1 then
              		return base;
		end if;
  
               if (even (exponent))  then
                   temp := pow (base, exponent / 2);
                   return temp * temp;
               end if;
               
               return base * pow (base, exponent - 1);
       
            end;