Compilare: user.cpp: In function ‘int nailed(long int)’: user.cpp:10:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] { for (int j=0;j<strlen(x);j++) ^ user.cpp: In function ‘int main()’: user.cpp:16:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0;i<strlen(y);i++) ^