incompatible types got boolean expected int64

I get this error on my insertion sort algorithm:

insertionsort.lpr(19,17) Error: Incompatible types: got «Boolean» expected «LongInt»

Here’s the line 19 of my code

I have tried googling all over the internet but i couldn’t find any syntax errors or anything.

Here’s the full code if it helps :

I also get the same error on the bubble sort algorithm i did. Here’s the error line

bubblesort.lpr(26,14) Error: Incompatible types: got «Boolean» expected «LongInt»

Here’s line 26 of my algorithm:

Here’s the full code:

1 Answer 1

In Pascal, boolean operators and and or have higher precedence than the comparison operators > , = , etc. So in the expression:

Given that and has higher precedence, Pascal sees this as:

0 and A[j] are evaluated as a bitwise and (since the arguments are integers) resulting in an integer. Then the comparison, j > (0 and A[j]) is evaluated as a boolean result, leaving a check of that with > key , which is boolean > longint . You then get the error that a longint is expected instead of the boolean for the arithmetic comparison.

The way to fix it is to parenthesize:

The same issue applies with this statement:

which yields an error because or is higher precedence than = . So you can parenthesize:

Or, more canonical for booleans:

When in doubt about the precedence of operators, parenthesizing is a good idea, as it removes the doubt about what order operations are going to occur.

var a, b, c, d, e :integer;

begin
readln (a);
b:= a mod 10;
c:= a mod 100 — b / 10;
d:= a div 100;
e:= b+c+d;
writeln (e);
end.

Error: Incompatible types: got «Extended» expected SmallInt.
Ашипка: Неподходящие типы: получил «Extended» вместо ожидаемого «SmallInt» 🙁

var a, b, c, delta, x1, x2 : integer

writeln(‘Tell me the value of a.’);

writeln(‘Tell me the valeu of b.’);

writeln(‘Tell me the value of c.’);

delta := (SQR(b) — 4*a*c);

2 Answers

The problem is caused by using floating point arithmetic when x1 is an integer.

Try using one of the following options:-

1. Use round(), floor(), trunc() type rounding functions

code becomes: «x1 := Round( (-b + SQRT(delta)) / 2*a );»