練習問題9.1

無限大の計算

public class Infinity {
	public static void main(String[] args) {
		Double pi = Double.POSITIVE_INFINITY;
		Double ni = Double.NEGATIVE_INFINITY;
		
		System.out.println("∞ + ∞  = " + (pi + pi));
		System.out.println("∞ + -∞ = " + (pi + ni));
		System.out.println("∞ - ∞  = " + (pi - pi));
		System.out.println("∞ - -∞ = " + (pi - ni));
		System.out.println("∞ * ∞  = " + (pi * pi));
		System.out.println("∞ * -∞ = " + (pi * ni));
		System.out.println("∞ / ∞  = " + (pi / pi));
		System.out.println("∞ / -∞ = " + (pi / ni));
	}
}

実行結果

∞ + ∞ = Infinity
∞ + -∞ = NaN
∞ - ∞ = NaN
∞ - -∞ = Infinity
∞ * ∞ = Infinity
∞ * -∞ = -Infinity
∞ / ∞ = NaN
∞ / -∞ = NaN