Compilare: user.c: In function ‘main’: user.c:25:12: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("int.in","r",stdin); ^ user.c:26:12: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("int.out","w",stdout); ^ user.c:29:10: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&n); ^ user.c:31:14: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&v[i].a,&v[i].b); ^ user.c:27:13: warning: ‘k’ may be used uninitialized in this function [-Wmaybe-uninitialized] int n,i,k,max=0,j1,j2,r,r2; ^