Compilare: user.cpp: In function ‘int verif(int, std::vector<int>)’: user.cpp:13:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0; i<=a.size()-l; i++) ^ user.cpp:22:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=a.size()-l+1; i<=a.size()-1; i++) ^ user.cpp:24:11: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(ctz==a.size()) return 1; ^ user.cpp: In function ‘void solve()’: user.cpp:40:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=1; i<=a.size()-1; i++) ^