Given a string of 0 and 1, we need to check that the given string is valid or not. The given string is valid when there is no zero is present in between 1’s. For example, 1111, 0000111110, 1111000 are valid strings but 01010011, 01010, 101 are not.
Input : 100 Output : VALID Input : 1110001 Output : NOT VALID There is 0 between 1s Input : 00011 Output : VALID
As we know that in a string if there is zero between 1’s, than string is not valid.Hence below is one of the regular expression for invalid string pattern.
So here is the simple regex algorithm.
- Loop over the matcher(string)
- if above regex match is find in the matcher, then string is not valid, otherwise valid.
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