Compilare: user.cpp: In function ‘int df()’: user.cpp:23: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘int main()’: user.cpp:48: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result user.cpp:50: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result