Compilare: main.cpp: In function 'int main()': main.cpp:4:39: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] #define rep(i, l, r) for(int i = l; i < r; ++i) main.cpp:42:13: rep(i, 0, sol.size()){ ~~~~~~~~~~~~~~~~ main.cpp:42:9: note: in expansion of macro 'rep' rep(i, 0, sol.size()){ ^~~ main.cpp:43:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(i+1<sol.size() && sol[i] == sol[i+1]) ~~~^~~~~~~~~~~