Compilare: main.cpp: In function 'int main()': main.cpp:52:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < base1.length() && ok == false; ++i) ok |= base1[i] == '1'; ~~^~~~~~~~~~~~~~~~ main.cpp:53:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < base2.length() && ok == false; ++i) ok |= base2[i] == '1'; ~~^~~~~~~~~~~~~~~~ main.cpp:54:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < base3.length() && ok == false; ++i) ok |= base3[i] == '1'; ~~^~~~~~~~~~~~~~~~ main.cpp:50:9: warning: unused variable 'sz1' [-Wunused-variable] int sz1 = base1.length(), sz2 = base2.length(), sz3 = base3.length(); ^~~ main.cpp:50:31: warning: unused variable 'sz2' [-Wunused-variable] int sz1 = base1.length(), sz2 = base2.length(), sz3 = base3.length(); ^~~ main.cpp:50:53: warning: unused variable 'sz3' [-Wunused-variable] int sz1 = base1.length(), sz2 = base2.length(), sz3 = base3.length(); ^~~