Hi Codeforces community. In this post I wan to tell about problem div2C/div1A. I waited for this round for a very long time, I sent my purposal 20th December. Approval came only 2 weeks ago, but some problems should be changed. Then I created a new problem (div2B), but I was unable to find something good about div1A. Then I remembered about my problem which was ready and was hidden in SPOJ. However, I today knew, that it was hidden, however problem could be found by link. I apologize to community and hope that you learned something or had fun solving other my problems.