I was having trouble with this problem: 584B - Коля и Таня, after a lot of trying I finally gave up, read the tutorial and found out that my solution was right. Confused, I tried a lot of stuff and rewrote my code several times but I couldn't get trough the same test case every time, then I changed the library from bits/stdc++.h to iostream and it worked! I sent it and finally got AC :D I couldn't believe that it was because of that, so I sent the same code with bits/stdc++.h and got WA. Here are those submissions: 14429081, 14429091

Why does that happen? Should I stop using bits/stdc++.h?

EDIT: sorry, It was a silly mistake :P