Compilare: user.cpp: In function ‘void suma(char*)’: user.cpp:17:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(i<strlen(s)) ^ user.cpp:24:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(i<strlen(s)) ^ user.cpp: In function ‘void produse(char*)’: user.cpp:43:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0; i<strlen(s); ++i) ^ user.cpp:57:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0; i<strlen(s); ++i) ^ user.cpp: In function ‘void adunare(char*)’: user.cpp:75:9: warning: unused variable ‘aux’ [-Wunused-variable] int aux; ^