Compilare: user.cpp: In function ‘int main()’: user.cpp:15:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=0;j<strlen(b)&&b[j]!='=';j++); ^ user.cpp:19:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=0;j<strlen(a);j++) ^ user.cpp:34:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=0;j<strlen(b);j++) ^