Compilare: user.cpp: In function ‘int main()’: user.cpp:14:10: warning: unused variable ‘c’ [-Wunused-variable] char c; ^ user.cpp:15:27: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%s\n", s); ^ user.cpp:16:26: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%s", s2); ^