10302 - Summation of polynomials/a.cpp

   1 /*
   2    Sebastian Arcila Valenzuela
   3    sebastianarcila@gmail.com
   4    2009
   5    @(#)TEMPLATE.c.tpl
   6  */
   7 #include <stdio.h>
   8 typedef unsigned long long ull;
   9 int main()
  10 {
  11   for(ull x,ans;scanf("%llu",&x) == 1; printf("%llu\n",ans*ans))
  12     if((x&1))
  13       ans = (x+1)/2*x;
  14     else
  15       ans = x/2*(x+1);
  16
  17   return 0;
  18 }
  19