Disabling syncing with C's stdio by using std::ios::sync_with_stdio(false) makes the C++ streams very fast (even faster than C's scanf/printf in many cases) allowing more elegant C++ solutions that don't suffer TLE. (like problem 1100). This should be in the FAQ.

http://stackoverflow.com/questions/1042110/using-scanf-in-c-programs-is-faster-than-using-cin