int d = getDigit(arr[i], digit);
Stream implementations can and do ignore backpressure; and some spec-defined features explicitly break backpressure. tee(), for instance, creates two branches from a single stream. If one branch reads faster than the other, data accumulates in an internal buffer with no limit. A fast consumer can cause unbounded memory growth while the slow consumer catches up — and there's no way to configure this or opt out beyond canceling the slower branch.
，详情可参考搜狗输入法2026
Photograph: Brad Bourque
The reason is that the compiler decided to allocate the backing store