How to print a int64 to screen?

[knapeczadam (Ádám Knapecz)]

int64 x = MAX_int64;
uint64 y = MAX_uint64;;
UE_LOG(LogTemp, Warning, TEXT("%lld"), x);
UE_LOG(LogTemp, Warning, TEXT("%llu"), y);
GEngine->AddOnScreenDebugMessage(INDEX_NONE, 5.0f, FColor::Cyan, FString::Printf(TEXT("%lld"), x));
GEngine->AddOnScreenDebugMessage(INDEX_NONE, 5.0f, FColor::Cyan, FString::Printf(TEXT("%llu"), y));