title: Determining complexity for recursive functions (Big O notation)
body: <p>I have a Computer Science Midterm tomorrow and I need help determining the complexity of these recursive functions. I know how to solve simple cases, but I am still trying to learn how to solve these harder cases. These were just a few of the example problems that I could not figure out. Any help would be much appreciated and would greatly help in my studies, thank you!</p>
  <pre><code>int recursiveFun1(int n)
  {
      if (n &lt;= 0)
          return 1;
      else
          return 1 + recursiveFun1(n-1);
  }
  
  int recursiveFun2(int n)
  {
      if (n &lt;= 0)
          return 1;
      else
          return 1 + recursiveFun2(n-5);
  }
  
  int recursiveFun3(int n)
  {
      if (n &lt;= 0)
          return 1;
      else
          return 1 + recursiveFun3(n/5);
  }
  
  void recursiveFun4(int n, int m, int o)
  {
      if (n &lt;= 0)
      {
          printf(&quot;%d, %d\n&quot;,m, o);
      }
      else
      {
          recursiveFun4(n-1, m+1, o);
          recursiveFun4(n-1, m, o+1);
      }
  }
  
  int recursiveFun5(int n)
  {
      for (i = 0; i &lt; n; i += 2) {
          // do something
      }
  
      if (n &lt;= 0)
          return 1;
      else
          return 1 + recursiveFun5(n-5);
  }
  </code></pre>