title: Way to insert charcters between two characters using Vi Editing unix
body: <p>Imagine two characters <code>n</code> and <code>1</code>, where I need to insert a new character between them. We just need to input commands (end with <kbd>Esc</kbd>) like <kbd>i</kbd>—insert before cursor. This command leaves vi in input mode until you press <kbd>Esc</kbd>.</p>
  
  <p>Now let's say there are range of two characters:</p>
  
  <ul>
  <li><code>n</code> and <code>1</code></li>
  <li><code>n</code> and <code>2</code></li>
  <li><code>n</code> and <code>3</code></li>
  <li><code>n</code> and <code>4</code></li>
  <li><code>n</code> and <code>5</code></li>
  <li><code>n</code> and <code>6</code></li>
  <li><code>n</code> and <code>8</code></li>
  <li><code>n</code> and <code>9</code></li>
  <li>...so on.</li>
  </ul>
  
  <p>e.g. "gin<code>Bulk</code>1" (added <code>Bulk</code> between <code>n</code> and <code>1</code>)</p>
  
  <p>Now I need to insert a UNIQUE character between these. So instead of manually going to each line one-by-one, pressing <kbd>i</kbd>, then inserting, can I just do it with simple command in vi?</p>