title: Python ValueError: too many values to unpack (expected 2)
body: <p>input</p>
  
  <pre><code> 2 4
   1 2 3 4
   1 0
   2 1
   2 3  
  </code></pre>
  
  <p>I need to extract the pairs of numbers from third line to the end(only 2 numbers from the third line)<br>
  here is my function  </p>
  
  <pre><code>def read_nodes():
      n, r = map(int, input().split())
      n_list = []
  
      for i in range(2 , n):
          n1, n2 = map(int, input().split())
          n_list.append([n1, n2])
      return n_list
  print(read_nodes())
  </code></pre>
  
  <p>I except <code>[[1,0],[2,1],[2,3]]</code>
  but says
  <code>ValueError: too many values to unpack (expected 2)</code></p>