Check if one string is a subsequence of another string.
Objective: Given two strings, write a program to check if any of the given string is a subsequence of another string. Example if given strings are A and B then EITHER A is subsequence of B OR B is subsequence of A, program should return true.
A = "horizon" B = "abhordizaonr" Output: true A = "abhordizaonr" B = "horizon" Output: true A = "abhor dizaonr" B = "horizon" Output: true A = "abordizaonr" B = "horizon" Output: false
- Given strings, A and B.
- Check if any of the string is null, return false.
- Compare the lengths of both the strings
- do String longer = A or B, whichever is longer than other.
- do String shorter = A or B, whichever is shorter than other.
- Now have two strings, longer and shorter. We know only a shorter string can be a subsequence of a longer string, whereas vice versa is not true.
- Initialize the starting index for the shorter string as j = 0.
- Iterate the longer string and for current index i
- If the character at index i in longer is the same as the character at index j in shorter. If yes then do j++.
- After iteration, if j==length of shorter means is subsequence in longer string, return true else return false.