Summer Memory

import java.io.*; public class Jamie02 { /** * @param args */ public static void main(String[] args) throws IOException { System.out.println("選擇形狀"); System.out.print("1.三角形 2.長方形 3.圓形= "); BufferedReader br = new BufferedReader(new InputStreamReader(System.in)); String str = br.readLine(); int C = Integer.parseInt(str); if (C>=4){ System.out.println("輸入錯誤重新啟動"); } if (C== 0){ System.out.println("輸入錯誤請重新啟動!!"); } if (C==1){ System.out.println("請問底為幾公分? "); String qwe = br.readLine(); double D = Double.parseDouble(qwe); System.out.println("請問高為幾公分? "); String ASD = br.readLine(); double A = Double.parseDouble(ASD); System.out.print("三角形面積為="+D*A/2); } if (C==2){ System.out.println("請問長為幾公分?"); String qwe = br.readLine(); double D = Double.parseDouble(qwe); System.out.println("請問寬為幾公分?"); String ASD = br.readLine(); double a = Double.parseDouble(ASD); System.out.print("長方型面積為="+D*a); } if (C==3){ System.out.println("請問半徑為幾公分?"); String qwe = br.readLine(); double D = Double.parseDouble(qwe); System.out.print("圓形面積為="+D*D*3.14); } } }