Marco Marco - 25 days ago 20
Pascal Question

Find the second highest value

I've wrote this Code to find out the second highest value in an Array:

var
i,
ZweitMax,
Max : integer;

begin
Max := -maxint;
ZweitMax := -maxint;

for i := 1 to FELDGROESSE do


if inFeld[i] > Max then
begin
ZweitMax := Max;
Max := inFeld[i];
end
else
if inFeld[i] > ZweitMax then
begin
ZweitMax := inFeld[i];
FeldZweitMax := ZweitMax;
end
end;


Where is the Problem in this Code and why it don't print out the right value?
Information: The Code is part of a function FeldZweitMax

Answer

There are currently two places where you set ZweitMax but only one of them also affects the return code of the function, FeldZweitMax.

The first part of the if statement can be changed into:

if inFeld[i] > Max then
begin
    ZweitMax := Max;
    FeldZweitMax := ZweitMax;  (* add this line *)
    Max := inFeld[i];
end
(* and so on *)

so as to ensure the return value is updated correctly.

Alternatively, you can just set ZweitMax alone in both places and then set the return value at the end:

for i := 1 to FELDGROESSE do
begin
    if inFeld[i] > Max then
    begin
        ZweitMax := Max;
        Max := inFeld[i];
    end
    else
    begin
        if inFeld[i] > ZweitMax then
        begin
            ZweitMax := inFeld[i];
        end
    end
end;
FeldZweitMax := ZweitMax;

I actually prefer the latter since the calculation and return of the value are separate matters.

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