Binary Exponentiation Algorithm Explained

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My name is Michael Lin and this is my programming youtube channel. I like C++ and please message me or comment on what I should program next. It really helps out a lot.

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[em_the_bee]

Recursively:
```
def b_exp(num, power)
return num if power == 1

# integer division, e. g. 7 / 3 returns 2
half_power = power / 2

# control for whether we can split the power evenly
one_or_num = power.even? ? 1 : num

half_exp = b_exp(num, half_power)
half_exp * half_exp * one_or_num
end
```

It works (on large numbers even faster than native Ruby method that's implemented in C), but how would you tail call optimise it?

Granted, it'll blow the stack only if your power is around 2^(your stack size) order of magnitude (i. e. really large), but still.

[tarundhouni]

hey man can we use this approch to solve fibonaci number

[RAMKUMAR-ebkq]

bro I cant understand the mod which you took last

[jintsuubest]

I do not understsand how this is less computation.
At the end, we are still flipping the same amount of bits when we are doing the last multiplication, no?

[MilindGupta]

hey, I checked your hackerrank profile and it showed you got c++ basic certificate but there is no skills test for c++ so how did you get those then?

[MinhHien-ntyx]

Sorry but I feel your explaination isn't good at all. cp-algorithms has all of this and I need a more detailed guidance from you.