以下是代码,目的就是要按输入数字的大小(即su),用rand函数随机输出a数组中的su个数,并且不能重复,我就卡在了不能重复哪里,怎么改代码都还是重复,求帮助
#include<stdio.h>
#include<stdlib.h>
#include<time.h>
#define M 10
void xuanqu(int a[],int changdu,int gesu);
int main(void)
{
    int a[M]={0,1,2,3,4,5,6,7,8,9};
    int chang;
    int su;
    char ch;


    while(1)
    {
    printf("please enter the su");
    scanf("%d",&su);
     getchar();
    xuanqu(a,M,su);
    printf("if you want to continue:");
    ch=getchar();
    if(ch=='y')
    continue;
    else
        break;

    }

return 0;
}

void xuanqu(const int a[],int changdu,int gesu)
{
    int i;
    int j;
    double zr;
    int inword=1;
    double ar[10];
srand(time(0));
    for(i=0;i<gesu;i++)
    {     zr=rand()%10;
        for(j=0;j<gesu;j++)
        {
            if(zr==a[j])
            {inword=0;
            break;}
            else
            continue;
        }
        if(inword=1)
        ar[j]=zr;
      printf("%3.2lf\n",zr);
    }
        
}

表示一名初学者没听说过散数列