sed extracting group of digits

Question

I have tried to extract a number as given below but nothing is printed on screen:

echo \"This is an example: 65 apples\" | sed -n  \'s/.*\\([0-9]*\\) apples/\\1/         


        

Answer 1

$ echo "This is an example: 65 apples" | sed -r  's/^[^0-9]*([0-9]+).*/\1/'
65