106 views
sequence of symbols from any part of the given string over an alphabet is called a substring

for abb

0length is epsilon

1 length is a,b

2 length is ab,bb

3 length is abb

how bb can be a substring because we have skipped a

if the above case is true then prefix is almost same to substring its a sequence of beginning symbols

0 length prefix is epsilon

1 length prefix is a,(why not b here can be a prefix over here above in two length string we are skipping a and taking bb as a two length substring )

+1 vote

1
2