Compilare: user.cpp: In function ‘int main()’: user.cpp:12:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=1;i<=strlen(b)/2;i++) ^ user.cpp:15:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=0;j<strlen(a);j++) ^ user.cpp:26:45: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(k=strlen(b)-i;k<strlen(b)&&ok==0;k++) ^