Compilare: user.cpp: In function ‘int main()’: user.cpp:41:11: warning: unused variable ‘m’ [-Wunused-variable] int n,m,a,b; ^ user.cpp:41:13: warning: unused variable ‘a’ [-Wunused-variable] int n,m,a,b; ^ user.cpp:41:15: warning: unused variable ‘b’ [-Wunused-variable] int n,m,a,b; ^ user.cpp:44:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("desen.out","w",stdout); ^