Compilare: user.cpp: In function ‘int main()’: user.cpp:27:10: warning: converting to non-pointer type ‘char’ from NULL [-Wconversion-null] *p=NULL; ^ user.cpp: In function ‘void rezolva(char*, long int&, long int&)’: user.cpp:58:17: warning: converting to non-pointer type ‘char’ from NULL [-Wconversion-null] {p[l-1]=NULL; ^ user.cpp: In function ‘int main()’: user.cpp:21:21: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin,"%d", &n); ^ user.cpp:24:28: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin,"%s", s1); ^