一個取n個不同的隨機數的演算法

//////////////////////////////////////////////////////////////////
// name:一個取n個不同的隨機數的演算法
// author:zhaoyongpeng
// date:2006.5.26
///////////////////////////////////////////////////////////////////
#include<iostream.h>
#include<stdlib.h>
#include<time.h>
int main()
{
       int a[100]={0};
       int i=0,length=0,value = 0;
    cout<<" 請輸入一個上限整數數值： ";
    cin>>value;
       cout<<"請輸入你想得到的互不相同的整數值(應該小於"<<value<<"):";
       cin>>length;

       bool flag=true;
       int temp=0;

  /* Seed the random-number generator with current time so that
   * the numbers will be different every time we run.
   */

       srand( (unsigned)time( NULL ) );
       for(i=0;i<length;i++)
       {
               temp=rand()%value;
               if(i!=0)
               {
                       flag=true;
                       while(flag)
                       {
                               flag=false;
                               for(int j=0;j<i;j++)
                               {
                                       if(a[j]== temp)
                                       {
                                               flag=true;
                                               temp=rand()%value;
                                               break;
                                       }
                               }
                       }
                       a[i]=temp;
               }
               else
               {
                       a[0]=temp;
               }
       }
for(i=0;i<length;i++)
       {
               cout<<a[i]<<"/t";
       }
cout<<endl;
       return 0;
}