actually this is incorrect and will fail in some random tests, but it passed...

would you please give some explaination? XD

yes, just realized the sign bit and '\0', thanks for your reply

i got you must return the given string error msg in random test,

need i consider the realloc?

emmm... i feel like a fool.

yes, it can. you need optimize your algo

how you come up with this solution...?

ok, just increase the precision -.-

In C++ random tests, it always failed like the follow:

Expected: equal to -7.601 (+/- 1e-06)
Actual: -7.601

what's the result supposed to be?

i've tried my knowledge of checking 2/3/4 squares sum but still failed with realy big random tests.. any tips?

yes, finally i chose the python version and passed

is the random test of c++ version broken?

Just curious about how you define those weights?

Thanks for the lession...