Disclaimer: I don't know Javascript, but that's why:

  > ['1','7','11'].map(console.log)
  1 0 [ '1', '7', '11' ]
  7 1 [ '1', '7', '11' ]
  11 2 [ '1', '7', '11' ]
  [ undefined, undefined, undefined ]
  
  > parseInt(1,0)
  1
  > parseInt(7,1)
  NaN
  > parseInt(11,2)
  3

The correct way is:

  > ['1','7','11'].map(x => parseInt(x))
  [ 1, 7, 11 ]

same as:

  > ['1','7','11'].map(x => parseInt(x, 10))
  [ 1, 7, 11 ]