Reduce accuracy of OS coordinates using regex

ngrs

#!/bin/bash

let tests=0
let fails=0

while read ngr expected
do
let tests=tests+1

out=$(echo $ngr | gawk '{
    $1 = gensub(/^(..)([0-9][0-9])...([0-9][0-9])...$/, "\\1\\2\\3", "", $1);
    $1 = gensub(/^(..)([0-9][0-9])..([0-9][0-9])..$/,"\\1\\2\\3", "", $1);
    $1 = gensub(/^(..)([0-9][0-9]).([0-9][0-9]).$/,"\\1\\2\\3", "", $1);
    print $1
}')
if [ "$out" = "$expected" ]
then
    echo "OK: $ngr got $out"
else
    echo "FAIL: $ngr got $out expected $expected" >&2
    let fails=fails+1
fi
done <<-!
TL1234567890    TL1267
TL12345678      TL1256
TL123456        TL1245
TL1234          TL1234
!

echo "$tests TESTS. $fails FAILURE(S)"
[ $fails -ne 0 ] && exit 1
exit 0