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;
}

Every Body has some problem in c++ in this problem...

Can Any body help...???!!!

First test has not to be the sample... you need only correct O(n) algo

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.

 eg mainc ar gava droshi arc C-ze.
 me aba CRASH-s madzlevs 39-e testze.
 sxva amoxseni rame.

 On PASCAL I got CRASH test #39
 On C++ the same solution got AC.