Need to duplicate text in each line and add equal sign and prefix to it

This is my text:

xxx
yyy
zzz

I would like it to be this text instead:

xxx = C.xxx
yyy = C.yy开发者_JS百科y
zzz = C.zzz

Is this possible to do in Vim?

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You can also use the simpler form:

:%s/.*/& = C.&

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Type this:

:%s/\(.*\)/\1 = c.\1/g

Breakdown:

• % - work on all lines
• \(.*\) - capture all the characters in a group ("group 1")
• s/PATTERN/REPLACEMENT/g - do a string substitution
• \1 in the replace pattern - refer to the matched group

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Select the text, then press : and type

s/\(.*\)/\1 = C.\1/