CODE 83. Pow(x, n)

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Implement pow(x, n).

public double pow(double x, int n) {
	// Note: The Solution object is instantiated only once and is reused by
	// each test case.
	boolean minus = false;
	double result = x;
	if (Math.abs(n - 0.0) < 1.0E-50) {
		return 1.0;
	} else if (Math.abs(x - 1.0) < 1.0E-50) {
		return 1.0;
	} else if (Math.abs(x + 1.0) < 1.0E-50) {
		if (n % 2 == 0) {
			return 1.0;
		} else {
			return -1.0;
		}
	}
	if (n < 0) {
		minus = true;
		n = -n;
	}
	for (int i = 1; i < n; i++) {
		result *= x;
		if (Math.abs(result) < 1.0E-50) {
			break;
		}
	}
	if (minus) {
		return 1 / result;
	} else {
		return result;
	}
}