It's a bug in FreePascal compiler. While reading a number Read/Readln fails if after number there is no new-line character.
FreePascal developers have already fixed this bug, but FreePascal version on Timus is not up-to-date. It will be updated soon.

such prog produces Fail(Validator)
(I understand that A!=B, but it is too long to 'guess' all output of my prog on the 1st test...)
#include <stdio.h>
int main()
{
        printf("5\n0 0\n0 0\n0 0\n0 0\n0 0\n");
        return 0;
};

This bug caused all problems of last day. I update FreePascal to 2.0.1. Now everything seems to be ok, but if you noticed some strange things, let me now.