title: How to test my program against an input test case file
body: <p>I was participating in some coding contests and luckily my code also ran. However my solution was not expected because i was wrong with the pattern of taking input. </p>
  
  <hr>
  
  <p>The question involved taking in an integer as an input and performing some operation and returning a different or same integer. I do not have any problem with the program, I just don't know how to code so as to take inputs like this</p>
  
  <hr>
  
  <pre><code>Input
  
  The input will contain several test cases (not more than 10). 
  Each test case is a single  line with a number n, 0 &lt;= n &lt;= 1 000 000 000. 
  It is the number given as input.
  
  Output
  
  For each test case output a single line, containing the integer returned.
  </code></pre>
  
  <hr>
  
  <pre><code>Example
  
  Input:
  12
  2
  
  Output:
  13
  2
  </code></pre>
  
  <hr>
  
  <p>My code is </p>
  
  <hr>
  
  <pre><code>#include &lt;stdio.h&gt;
  
  int functionReturningInteger(int n)
  {
  // implementation
  ........ 
  return num;
  }
  
  
  int main(void)
  {
  
  int number;
  //printf("Enter the number: ");
  scanf("%d",&amp;number);
  printf(functionReturningInteger(number));
  return 0;
  </code></pre>
  
  <p>}</p>
  
  <hr>
  
  <p>How am i supposed to know how many inputs they will give ( although they do provide a maximum limit). And if i use an array to store these inputs whose size is equal to the maximum limit, how do i check the size of an integer array in c ?</p>
  
  <hr>
  
  <p>I will appreciate anybody helping out with a small piece of code. Also if am able to test it against an input test file and generate an "output.txt" (output file). I already have the desired output file "des.txt". Then how can i match whether both the files are same or not ?</p>