title: Binary Absolute value
body: <p>If I want to represent a number in binary with absolute value and its sign I do this:
  F.e. 3 = 11 -> 011 (0 because it's positive)
  -7 = 111 -> 1111 (I added a 1 because it's negative).</p>
  
  <p>If I have this situation and I represent the numbers in binary with sign and absolute value</p>
  
  <p>-3 = 11 -> 111
  -7 = 111 -> 1111</p>
  
  <p>and then I want to sum them</p>
  
  <p>1111 +
     111 =
  ....</p>
  
  <p>is this format correct? 
  Because -3 is shorter than -7 in binary and if I add a zero in this way</p>
  
  <p>1111 +
  0111 =
  ....</p>
  
  <p>will I lose the sign of -3?</p>