From 99b7c30807d66bfe10ca88a60fb4da2f9be39066 Mon Sep 17 00:00:00 2001
From: onceupon <nim.1111.ou@gmail.com>
Date: Wed, 11 Apr 2018 10:00:37 +0800
Subject: [PATCH] add sed

Remove lines whose nth character not equal to a value
---
 README.md | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/README.md b/README.md
index c49ed3b..ddfa10b 100644
--- a/README.md
+++ b/README.md
@@ -194,6 +194,12 @@ sed "/bbo/d" filename
 - case insensitive:
 sed "/bbo/Id" filename
 ```
+##### Remove lines whose nth character not equal to a value (e.g. 5th character not equal to 2)
+```bash
+sed -E '/^.{5}[^2]/d'
+#aaaa2aaa (you can stay)
+#aaaa1aaa (delete!)
+```
 
 ##### Edit infile (edit and save)