title: Declaring arrays in c language without initial size
body: <p>Write a program to manipulate the temperature details as given below.<br>
  - Input the number of days to be calculated. – Main function<br>
  - Input temperature in Celsius – input function<br>
  - Convert the temperature from Celsius to Fahrenheit.- Separate function<br>
  - find the average temperature in Fahrenheit.  </p>
  
  <p>how can I make this program without initial size of array ??</p>
  
  <pre><code>#include&lt;stdio.h&gt;
  #include&lt;conio.h&gt;
  void input(int);
  int temp[10];
  int d;
  void main()
  {
      int x=0;
      float avg=0,t=0;
      printf("\nHow many days : ");
      scanf("%d",&amp;d);
      input(d);
      conv();
      for(x=0;x&lt;d;x++)
      {
          t=t+temp[x];
      }
      avg=t/d;
      printf("Avarage is %f",avg);
      getch();
  }
  void input(int d)
  {
      int x=0;
      for(x=0;x&lt;d;x++)
      {
          printf("Input temperature in Celsius for #%d day",x+1);
          scanf("%d",&amp;temp[x]);
      }
  }
  void conv()
  {
      int x=0;
      for(x=0;x&lt;d;x++)
      {
          temp[x]=1.8*temp[x]+32;
      }
  }
  </code></pre>