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In java, will the program “remember” the result if you call the same function a second time?

This question arose when I thought of an algorithm to quickly calculate the power of a number, for example to calculate x^n.

In Java, the recursive part looks something like this:

return power(x,n/2) * power(x,n/2);

So, after the program returns the value power(x,n/2), will it again run the entire recursive process to calculate the value for the second power(x,n/2)?

If so, should you first store the value in a variable and then return the square of that value?

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7 answers

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// compute pow(base, exponent)

int result = 1;
int term = base;

while (exponent != 0)
{
  if (exponent % 2 != 0) { result *= term; }
  term = term * term;
  exponent /= 2;
}

return result;

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