Compilare: user.cpp: In function ‘void read()’: user.cpp:8: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result user.cpp:13: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result user.cpp: In function ‘int calc(int, int)’: user.cpp:21: warning: unused variable ‘j’ user.cpp: In function ‘void modif(int, int, int&)’: user.cpp:30: warning: unused variable ‘j’