Compilare: main.cpp: In function 'int main()': main.cpp:37:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0; j < v[i%4].size(); j ++) { ~~^~~~~~~~~~~~~~~ main.cpp:41:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0; j < aux.size(); j ++) { ~~^~~~~~~~~~~~ main.cpp: In function 'int convert(char)': main.cpp:15:1: warning: control reaches end of non-void function [-Wreturn-type] } ^