Power

Power

Find x to the power n in efficient way. Assume that x>=0 and n>=0.

Sol:

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int power(int x, int n)    {     if(n <= 0)         return 1;     else if(n == 1)         return x;     else if(n%2 == 0)         return power(x*x, n/2);     else         return x*power(x*x, n/2); }

If x is double and n is integer

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public static double power(double x, int n)  {   if(n<0){       return 1/(x* power(x, -(++n)));    }    else if(n == 0) {        return 1;    }    else {        return (n%2 == 0) ? power(x*x, n/2) : x* power(x*x, n/2);    } }