求最大公约数的算法

Yemoo'S Java Blog — Wed, 06 Dec 2006 17:02:00 GMT

/**
*Description:greatest common divisor
*Author:yemoo 2006.12.06
*/

public class Pt32{
     // 思路：辗转相除法
      int divisor1( int m, int n){     // 方法一：循环法
          int temp;
          if (m < n){     // if m
             temp = m;
             m = n;
             n = temp;
         }
          while (m % n != 0 ){
             temp = n;
             n = m % n;
             m = temp;
         }
          return n;
     }

      int divisor2( int m, int n){     // 方法二：递归法
          int temp;
          if (m < n){
             temp = m;
             m = n;
             n = temp;
         }
          return divisor22(m,n);
     }

     int divisor22( int m, int n){
         if (m % n == 0 ){
             return n;
        } else {
             return divisor22(n,m % n);
        }
    }

      public static void main(String args[]){
         KeyboardInput in = new KeyboardInput();
         Pt32 obj = new Pt32();
         System.out.println( " input two integer: " );
          int a = in.readInt();
          int b = in.readInt();
         System.out.println(a + " , " + b + " 's greatest common divisor is " + obj.divisor2(a,b));
     }

}

使用了辗转相除法，分别使用循环和递归方法实现。

吸取dreamstone大哥的程序写法，发现判断m、n大小的部分可以删除，因为如果m
改进后程序代码（精简了好多哦）：

/**
*Description:greatest common divisor
*Author:yemoo 2006.12.07 */

public class Pt32{
    //思路：辗转相除法
     int divisor1(int m,int n){    //方法一：循环法
         int temp;
         while(m%n!=0){
             temp=n;
             n=m%n;
             m=temp;
         }
         return n;
     }

     int divisor2(int m,int n){    //方法二：递归法
         if(m%n==0){
            return n;
        }else{
            return divisor2(n,m%n);
        }
     }

     public static void main(String args[]){
         KeyboardInput in=new KeyboardInput();
         Pt32 obj=new Pt32();
         System.out.println("input two integer:");
         int a=in.readInt();
         int b=in.readInt();
         System.out.println(a+","+b+"'s greatest common divisor is "+obj.divisor2(a,b));
     }

}

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求最大公约数的算法