title: How to accept case-insensitive inputs?
body: <p>How do you accept case-insensitive and allow embedded blanks in a user input? So the user can enter “hong konG” and get a correct match to the input.</p>
  
  <p>I only have the <code>input[0] = toupper(input[0]);</code> which only accepts if the case sensitive is at the beginning of the word.</p>
  
  <pre><code>while(true){
  cout &lt;&lt; "Enter a city by name: "&lt;&lt; " "; 
  std::getline (std::cin,input);
  if (input == "quit")
      {
          break;
      }
  input[0] = toupper (input[0]);
  
      //....how do I loop to find all letter's in the input string variable?    
  }
  </code></pre>