Compilare: main.cpp: In function 'std::vector<char> concatenare(int, std::vector<char>)': main.cpp:19:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j=0;j<v.size();j++) ~^~~~~~~~~ main.cpp: In function 'std::vector<char> palind_par(std::vector<char>)': main.cpp:27:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0;i<v.size();i++) ~^~~~~~~~~ main.cpp: In function 'std::vector<char> palind_imp(std::vector<char>)': main.cpp:37:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0;i<v.size();i++) ~^~~~~~~~~ main.cpp: In function 'std::vector<char> conct_norm(std::vector<char>, std::vector<char>)': main.cpp:51:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0;i<v.size();i++) ~^~~~~~~~~ main.cpp:53:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0;i<w.size();i++) ~^~~~~~~~~ main.cpp: In function 'int main()': main.cpp:146:11: warning: suggest parentheses around '+' inside '>>' [-Wparentheses] fin>>v+1; ~^~ main.cpp:198:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0;i<sol.size();i++) ~^~~~~~~~~~~