Best way to do powerOf(int x, int n)?

Posted by Mike on Stack Overflow See other posts from Stack Overflow or by Mike
Published on 2010-03-30T02:29:15Z Indexed on 2010/03/30 2:33 UTC
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So given x, and power, n, solve for X^n. There's the easy way that's O(n)... I can get it down to O(n/2), by doing

numSquares = n/2; numOnes = n%2; return (numSquares * x * x + numOnes * x);

Now there's a log(n) solution, does anyone know how to do it? It can be done recursively.

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