title: C, checking if the first character of an input is a certain letter
body: <p>For an assignment I need to receive an input (in C), always starting with a letter and followed by either a space or \n, like for example</p>
  <pre>
  A 123456 abcde
  B 123
  C
  </pre>
  <p>These letters are used to define which function to call and the following info will be the parameters used in the function.</p>
  <p>I'm having major difficulties receiving the input and then moving forwards.
  I've tried splitting the input at &quot; &quot; with strtok and making it into an array but can't really get anywhere with that. I also can't find a way to check if an element of the array is a certain letter like:
  if ((str[0] == &quot;A&quot;) != 0) { --&gt;</p>
  <p>any suggestions? &lt;3</p>