On Thu, 18 Jul 2024 14:39:16 GMT, fabioromano1 <[email protected]> wrote:
>> src/java.base/share/classes/java/math/MutableBigInteger.java line 1973:
>>
>>> 1971:
>>> 1972: /* For every long value s in [0, 2^32) such that x == s *
>>> s,
>>> 1973: * it is true that s == Math.round(Math.sqrt(x >= 0 ? x :
>>> x + 0x1p64)),
>>
>> To reinforce this claim, I suggest to add a test for all perfect squares.
>
> I did it, although I'm afraid it takes up too much running time due to the
> overhead of BigInteger's wrapping...
I mean only restricted to unsigned `long` perfect squares, something like the
following, but written as a proper test
long i = 0;
for (; i < 1L << 32; ++i) {
long x = i * i;
long s = (long) Math.sqrt(x >= 0 ? x : x + 0x1p64);
if (!(s + 1 == i || s == i)) {
System.out.format("oops... i=%d, but s=%d%n", i, s);
System.exit(1);
}
}
-------------
PR Review Comment: https://git.openjdk.org/jdk/pull/19710#discussion_r1682989536
