Compilare: user.c: In function ‘G’: user.c:12:19: warning: operation on ‘i’ may be undefined [-Wsequence-point] if(P[i]<P[j])i^=j^=i^=j; ^ user.c: In function ‘main’: user.c:17:12: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("disjoint.in","r",stdin); ^ user.c:18:12: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("disjoint.out","w",stdout); ^ user.c:20:10: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%i%i",&n,&m); ^ user.c:24:14: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%i%i%i",&t,&a,&b);--a,--b; ^