Compilare: main.cpp: In function 'int main()': main.cpp:37:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(pal1.size() < l) ~~~~~~~~~~~~^~~ main.cpp:41:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(pal1.size() + 2 >= l) ~~~~~~~~~~~~~~~~^~~~ main.cpp:65:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(pal2.size() < n - l) ~~~~~~~~~~~~^~~~~~~