var cnt = 0
 
for m in 1 .. 12:
  let x = case m:
    of 2: 28
    of 4, 6, 9, 11: 30
    else: 31
  for d in 1 .. x:
    let
      d1 = d div 10
      d2 = d mod 10
    if d1 + d2 == m: inc cnt
 
echo cnt