powerapp.java

此程序可以让用户通过递归的方式解答数的乘方问题

//power.java

import java.io.*;
///////////////////////////////////////////////////
public class PowerApp
{
static int a;
static int n;

public static void main(String[] args) throws IOException
      {
      System.out.print("输入底数a: ");
      int a = getInt();
       System.out.print("输入指数n: ");
      int n = getInt();
      int theAnswer = Power( a,n);
      System.out.println("a 的 n 次方="+theAnswer);
    }
    public static int Power(int a,int n)
      {
          if (a==0)
          return 0;
         else if (n==0)
          return 1;
          else
          return  ( a*Power(a,(n-1)) );
      }
//-------------------------------------------------------------
   public static String getString() throws IOException
      {
      InputStreamReader isr = new InputStreamReader(System.in);
      BufferedReader br = new BufferedReader(isr);
      String s = br.readLine();
      return s;
      }
//-------------------------------------------------------------
   public static int getInt() throws IOException
      {
      String s = getString();
      return Integer.parseInt(s);
      }
//--------------------------------------------------------------
   }  // end class PpwerApp
////////////////////////////////////////////////////////////////