夜半饼干
幼苗
共回答了17个问题采纳率:82.4% 举报
class circle{ public circle(int r){ R=r; } private double R; public double getalllong(){ return 2*Math.PI*R; } public double getarea(){ return Math.PI*R*R; } } public static void main(String[] a){ circle r=new circle(2.5); System.out.println("周长:"+r.getalllong()+"面积:"+r.getarea()); }
1年前
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