sed：在n个字符的字符串的开头替换字符

Question

I have:

12223335566
19988776655
9918877665566
44410007777222
etc

I am trying to find the sed syntax for replacing 1 with nothing only when 1 is at the beginning of a string composed of 10 digits so that the above input should look like this:

2223335566
9988776655
9918877665566
44410007777222

As you can see, the replacement should occur only in the first two strings, leaving the other two untouched because even though the 1 in them is followed by 10 digits, it is not at the beginning.

Answer 1

使用sed

sed -r 's/^1([0-9]{10})$/\1/' file

Answer 2

要从11位数字中删除开头1：

sed 's;^1\([0-9]\{10\}\)$;\1;' filename

Answer 3

Here is an awk solution

cat file
12223335566
19988776655
1245245543
14545klk342
9918877665566
44410007777222

awk '$1+0>10000000000 && $1+0<199999999999 {sub(/^1/,x)}8' file
2223335566
9988776655
1245245543
14545klk342
9918877665566
44410007777222