Regular Expressions 101

Pro

\ban ASCII word boundary

2the literal 2 (50₁₀ / 62₈ / 32₁₆)

6?optionally matches the literal 6 (54₁₀ / 66₈ / 36₁₆)

Group 1([^7]6|8|[^6]7)+?

+?repeats the group contents below at least once:

1st Alternative[^7]6

Negated Character Class[^7]

7the literal 7 (55₁₀ / 67₈ / 37₁₆)

6the literal 6 (54₁₀ / 66₈ / 36₁₆)

2nd Alternative8

8the literal 8 (56₁₀ / 70₈ / 38₁₆)

3rd Alternative[^6]7

Negated Character Class[^6]

6the literal 6 (54₁₀ / 66₈ / 36₁₆)

7the literal 7 (55₁₀ / 67₈ / 37₁₆)

4the literal 4 (52₁₀ / 64₈ / 34₁₆)

\ban ASCII word boundary

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.

25 tokens

Regular Expression

\b26?([^7]6|8|[^6]7)+?4\b

New

Samples of valid strings are like  26874
'266868874', '268787866668887774', '268688788774'. 26666868886688874
'26878787868888666878868686866668688887888687774'
Invalid strings are like '263874', '268734', '2688668778868714', etc...  2324235235980980
26876874 You CAN NOT transit from 7 to 6 in one step. Only '7-8-6-8-7-4' would happen, not '7-6-8-7-4'