Compilare: user.cpp: In function ‘void ve(int&, char*)’: user.cpp:17:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(x[t]!=')'&&t<strlen(x)) ^ user.cpp: In function ‘int main()’: user.cpp:89:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=0;j<strlen(r[i]);j++) ^