I got TLE, but when i used Visual C++ 2010 I hot AC. It worked for me, I hope it will work also for you

Thank you so much for the tip. Worked fine for me as well.

Task is compiler-independent.

Here are successful GCC runs in my recent successful runs:
7147656, 0.249 sec - using printf/scanf;
7147682, 0.28 sec - using IO streams and std::ios_base::sync_with_stdio(false).

I think it would be great to modify http://acm.timus.ru/help.aspx?topic=cpp
article - add "G++ only section" and strongly advice to use "std::ios_base::sync_with_stdio(false)" with IO streams.

Details are (for example) here:
https://habrahabr.ru/post/246257/

I also had the same mistake, use "ios_base::sync_with_stdio(false);" and get AC