Compilare: main.cpp: In function 'void radix_sort(int)': main.cpp:29:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < current_suffixes.size(); ++ i) ~~^~~~~~~~~~~~~~~~~~~~~~~~~ main.cpp:44:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < current_suffixes.size(); ++ i) ~~^~~~~~~~~~~~~~~~~~~~~~~~~ main.cpp: In function 'int suffix_arrays(std::__cxx11::string&, int)': main.cpp:67:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < current_suffixes.size(); ++ i) ~~^~~~~~~~~~~~~~~~~~~~~~~~~ In file included from /usr/include/c++/6/cassert:44:0, from /usr/include/x86_64-linux-gnu/c++/6/bits/stdc++.h:33, from main.cpp:1: main.cpp: In function 'int main()': main.cpp:141:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] assert(n == sorted.size()); ~~^~~~~~~~~~~~~~~~