Help needed ,Doubt in video solution

#1

Does dp[i][j-2] here j starts from 1 ,so 1-2==-1?? index j becomes negative at some point of time

#2

This can occur only when the pattern begins with a ’ * '. I think the pattern will never start with a ’ * ’
Or you can handle this case seperately.

#3

@pratyush63 Sir Can U please provide with additional changes for “you can handle this case seperately?”

#4

No…the code is correct.
It is guaranteed that pattern will not begin with a “*”
You can submit your code here and check https://leetcode.com/problems/regular-expression-matching/

#5

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