Compilare: user.cpp: In function ‘void suma()’: user.cpp:20:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(i<strlen(s)) ^ user.cpp:27:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(i<strlen(s)) ^ user.cpp: In function ‘void produse()’: user.cpp:46:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0; i<strlen(s); ++i) ^ user.cpp:60:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0; i<strlen(s); ++i) ^