Bash count number of numbers

Question

I have several space separated strings:

1 -2 3  
1 23 456  
apple 69 b4n4n45 gr4pe5 -420 lol 10101010101 lol
1 23 a99 99a 9a9 -1 -23 -a99 -99a -9a9 --1 --23 --a99 --99a --9a9

I would like to know the exact number of numbers in each one of these strings. For the examples above the answers should be [ 3, 3, 3, 4]. I would not like to count strings like b4n4n45 as "numbers". Only pure integer strings should be counted.

I tried using grep and regex:

$ echo $string | grep '[0-9]' | wc

but that's not working out for me. Any tips?

Answer 1

Could you please try following(tested and written with shown samples), this should include negative numbers too, since OP has mentioned about integers so I have not considered counting floats. It gives output as 3 3 3 for mentioned 3 lines of samples.

awk '
{
  for(i=1;i<=NF;i++){
    if(length(int($i))==length($i)){ count++ }
  }
  print count
  count=""
}' Input_file