Compilare: main.cpp: In function 'void add(std::vector<int>&, std::vector<int>&)': main.cpp:12:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0; i<b.size() or val; i++){ ~^~~~~~~~~ main.cpp:13:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (i < b.size()) val += b[i]; ~~^~~~~~~~~~ main.cpp:14:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (i < a.size()){ ~~^~~~~~~~~~ main.cpp: In function 'void multiply(std::vector<int>&, int)': main.cpp:28:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0; i<a.size() or val; i++){ ~^~~~~~~~~ main.cpp:29:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (i < a.size()){ ~~^~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:48:15: warning: unused variable 'j' [-Wunused-variable] int n, i, j; ^