Regular Expressions 101

Group 1([A-Z])

Character Class[A-Z]

A-Zone character from A (65₁₀) to Z (90₁₀) (case sensitive)

\1{2}the text saved by group 1, repeated exactly 2 times

Negative Lookahead(?!\1)

\1the text saved by group 1

Group 2([A-Z])

Character Class[A-Z]

A-Zone character from A (65₁₀) to Z (90₁₀) (case sensitive)

\2{2}the text saved by group 2, repeated exactly 2 times

Negative Lookahead(?!\1|\2)

1st Alternative\1

\1the text saved by group 1

2nd Alternative\2

\2the text saved by group 2

Group 3([A-Z])

Character Class[A-Z]

A-Zone character from A (65₁₀) to Z (90₁₀) (case sensitive)

\3{2}the text saved by group 3, repeated exactly 2 times

Negative Lookahead(?!\1|\2|\3)

1st Alternative\1

\1the text saved by group 1

2nd Alternative\2

\2the text saved by group 2

3rd Alternative\3

\3the text saved by group 3

Group 4([A-Z])

Character Class[A-Z]

A-Zone character from A (65₁₀) to Z (90₁₀) (case sensitive)

\4{2}the text saved by group 4, repeated exactly 2 times

Global pattern flags

g modifier: global. Finds all matches instead of stopping after the first

m modifier: multiline. Causes ^ and $ to match the start and end of each line, not only the start and end of the string

Detailed match information will be displayed here automatically.

Search reference

Regular Expression

([A-Z])\1{2}(?!\1)([A-Z])\2{2}(?!\1|\2)([A-Z])\3{2}(?!\1|\2|\3)([A-Z])\4{2}

New

AAABBBCCCDDD
BBBAAADDDCCC
CCCAAABBBDDD
AAABBBAAABBB
AAAAAAAAAAAA