Given a string s and a string t, check if s is subsequence of t.
You may assume that there is only lower case English letters in both s and t. t is potentially a very long (length ~= 500,000) string, and sis a short string (<=100).
A subsequence of a string is a new string which is formed from the original string by deleting some (can be none) of the characters without disturbing the relative positions of the remaining characters. (ie,
"ace" is a subsequence of "abcde" while "aec" is not).
Example 1:
s =
s =
"abc", t = "ahbgdc"
Return
true.
Example 2:
s =
s =
"axc", t = "ahbgdc"
Return
false.
Follow up:
If there are lots of incoming S, say S1, S2, ... , Sk where k >= 1B, and you want to check one by one to see if T has its subsequence. In this scenario, how would you change your code?
------------------If there are lots of incoming S, say S1, S2, ... , Sk where k >= 1B, and you want to check one by one to see if T has its subsequence. In this scenario, how would you change your code?
没啥好说的
class Solution {
public boolean isSubsequence(String s, String t) {
int i = 0, j = 0;
while (i < s.length() && j < t.length()) {
char c1 = s.charAt(i);
char c2 = t.charAt(j);
if (c1 != c2) j++;
else {
i++;
j++;
}
}
return i == s.length();
}
}
