awk

  1. echo "1:3:5" | awk -F ":" '{print $NF}'

  1. echo 'https://studygolang.com/dl/golang/go1.15.8.linux-amd64.tar.gz' | awk -F "/" '{print $NF}'

sed

  1. echo "1:3:5" | sed 's/.*:\([^:]*\)$/\1/'