Compilare: user.cpp: In function ‘int main()’: user.cpp:80:9: warning: unused variable ‘i’ [-Wunused-variable] int i,q,w; ^ user.cpp:80:11: warning: unused variable ‘q’ [-Wunused-variable] int i,q,w; ^ user.cpp:80:13: warning: unused variable ‘w’ [-Wunused-variable] int i,q,w; ^ user.cpp:79:22: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d",&n); ^