In round #85 div 2, question A using this function was very helpful
cout << strcasecmp(a,b) << endl;
Here are some more useful functions found in gnu extensions, but not in standard library
__typeof()
#define REP(i,n) for (__typeof(n) i = 0; i < n; ++i)
__builtin_popcount(n) - counts the number of set bits in n. Example, for 10 it prints 2.
Are there anymore gnu extensions which you find useful? And what's codeforces policy on that?
