You can find the solution of Problem A Div1 as soon as you search about it.

You can see this link

you've to add just one condition and get problem accepted

if(i == pp.first || i == pp.second || j == pp.first || j == pp.second) continue;

Therefore, this is unfair to some of the contestants.

Is it possible to find a solution ???

ch_egor

MikeMirzayanov