有1、2、3、4個(gè)數(shù)字，能組成多少個(gè)互不相同且無重復(fù)數(shù)字的三位數(shù)？都是多少？

package demo;/** * Created by asus on 2017/2/7. */public  class HelloWorld {    public static void  main(String []args){        int count=0;        int []a={1,2,3,4};        int []b={1,2,3,4};        int []c={1,2,3,4};        for (int i=0;i<a.length;i++){            for (int m=0;m<b.length;m++){                for (int n=0;n<c.length;n++){                    if ((a[i]!=b[m])&&(a[i]!=c[n])&&b[m]!=c[n]){                        System.out.PRint(a[i]);                        System.out.print(b[m]);                        System.out.println(c[n]);                        count++;                    }                }            }        }        System.out.println("count="+count);    }}