title: Getting an integer value from string in c++
body: <p>I am trying to learn c++, and for an assignment I have ran into a problem. I am trying to get an integer value from a string that a user enters all on one line. </p>
  
  <p>Ex.) The user inputs: "Change value to 15."</p>
  
  <p>What is the best way of getting the 15 from that string? I have looked around for a while, but could only find if a string was only integers.</p>
  
  <p>Thanks in advance!</p>