Compilare: main.cpp: In function 'int main()': main.cpp:22:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0;i<strlen(c);i++) ~^~~~~~~~~~ main.cpp:27:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (i<strlen(c) && litera(c[i+1])) ~^~~~~~~~~~ main.cpp:33:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (i<strlen(c) && semn(c[i+1])) ~^~~~~~~~~~