Compilare: user.c: In function ‘main’: user.c:34:23: warning: unused variable ‘j’ [-Wunused-variable] int n,t,i,k,k1,k2,j; ^ user.c:34:20: warning: unused variable ‘k2’ [-Wunused-variable] int n,t,i,k,k1,k2,j; ^ user.c:34:17: warning: unused variable ‘k1’ [-Wunused-variable] int n,t,i,k,k1,k2,j; ^ user.c:32:12: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("linterv.in","r",stdin); ^ user.c:33:12: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("linterv.out","w",stdout); ^ user.c:35:10: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&t); ^ user.c:37:14: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&n); ^ user.c:39:18: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&v[i].x,&v[i].y); ^