Compilare: user.cpp: In function ‘void ins(int)’: user.cpp:37:6: warning: unused variable ‘i’ [-Wunused-variable] {int i; ^ user.cpp: In function ‘void del(int)’: user.cpp:48:6: warning: unused variable ‘i’ [-Wunused-variable] {int i; ^ user.cpp: In function ‘int main()’: user.cpp:60:20: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] {fscanf(f1,"%d",&n); ^ user.cpp:62:20: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] {fscanf(f1,"%d",&o); ^ user.cpp:63:30: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] if (o==1) {fscanf(f1,"%d",&x);ins(x);} ^ user.cpp:64:35: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] else if (o==2) {fscanf(f1,"%d",&x);del(x);} ^