Pascal got TLE on 40 test, but c++ WA on test 1 whyyy

Wrong Answer On Test 1

help...

#include <fstream>
#include <iostream>
using namespace std;

int main(void) {
long int st[40001], n, l, a, b, i, j;

cin >> n;

for (i=0; i<40001; i++)
st[i] = -2;

for (i=0; i<n; i++) {
cin >> a >> b;
st[a] = b;
}

cin >> l;

for (j=0; j<l; j++) {
cin >> a >> b;

i = a;
while (i >= 0 && i != b)
i = st[i];

if (i == b) {
cout << "2\n";
continue;
}

i = b;
while (i >= 0 && i != a)
i = st[i];

if (i == a) {
cout << "1\n";
continue;
}

cout << "0\n";
}
return 0;
}



I know this algorithm is not so good, but I am disapointed because Pascal Program with this algo got TLE on 40 test, but C++ program got WA on test 1. why ?


Pascal Programm:
var l, i, j, n, a, b: longint;
st: array[0..40000] of longint;

begin

for i := 0 to 40000 do
st[i] := -2;

readln(n);
for i := 1 to n do begin
readln(a, b);
st[a] := b;
end;

readln(l);
for j := 1 to l do begin
readln(a, b);

i := a;
while i >= 0 do begin
i := st[i];
if (i = b) then break;
end;
if i = b then begin writeln(2); continue; end;

i := b;
while i >= 0 do begin
i := st[i];
if (i = a) then break;
end;
if i = a then begin writeln(1); continue; end;

writeln(0);
end;

end.