12/05 進階程式設計 練習一

#include <stdio.h>
#include <stdlib.h>
#include<time.h>
int main(void)
{
    int no[100],i,count;
    int *ptr1;   //用來產生亂數的指標
    int *ptr=no;  //用來走訪陣列的指標
    srand(time(NULL));
    FILE *written;
    written=fopen("random.txt","w");

    for(i=1;i<=10;i++)
    {

       *ptr1=rand()%100;
       fprintf(written,"%d ",*ptr1);


    }

    fclose(written);
    printf("寫檔完成\n\n");


    printf("**讀檔**\n\n");
    FILE *read01;
    count=0;
    read01=fopen("random.txt","r");

   while(!feof(read01))
   {
      count++;
      fscanf(read01,"%d",&no[count]);
   }
   fclose(read01);

   ptr=&no[1];

     for(i=1;i<=10;i++)
    {
        printf("值:(%d),位址:(%p)\n",*ptr,ptr);
        ptr++;
    }

    int sum=0,avg=0;
    int *ptr_avg=&avg, *ptr_sum=&sum;

    ptr=&no[1];
    for(i=1;i<=10;i++)
    {
       *ptr_sum=*ptr_sum+*ptr;
       ptr++;
    }

    printf("\n==========================\n");
    *ptr_avg=(float)*ptr_sum/10;
    printf("總和值為:%d,位址:(%p)\n",*ptr_sum,ptr_sum);
    printf("平均值為:%d,位址:(%p)\n",*ptr_avg,ptr_avg);
    printf("\n==========================\n");




    system("pause");
    return 0;
}