Compilare: user.cpp: In function ‘void heapdown(int&)’: user.cpp:36:13: warning: unused variable ‘x’ [-Wunused-variable] int i,j,x; ^ user.cpp: In function ‘void heapsort(int)’: user.cpp:51:11: warning: unused variable ‘j’ [-Wunused-variable] int i,j,ncr=n; ^ user.cpp: In function ‘int main()’: user.cpp:77:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("apm.in","r",stdin); ^ user.cpp:78:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("apm.out","w",stdout); ^ user.cpp:81:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&n,&m); ^ user.cpp:84:54: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d",&(v[i].x),&(v[i].y),&(v[i].c)); ^