原題目:
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 s is 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 = "abc"
, t = "ahbgdc"
Return true
.
Example 2:
s = "axc"
, t = "ahbgdc"
Return false
.
class Solution {
public:
bool isSubsequence(string s, string t) {
int j = 0, l1 = s.length(), l2 = t.length();
for(int k=0; k<l2&&j<l1; k++)
if(t[k]==s[j]) j ++;
return j==l1;
}
};