Merge pull request #504 from 0chnxxx/0chnxxx/ltc/392

[LTC] Lv1 / Is Subsequence / 7분

Author: 0chnxxx

leetcode/0chnxxx/Is_Subsequence.kt

@@ -0,0 +1,42 @@
+/**
+ * Given two strings s and t, return true if s is a subsequence of t, or false otherwise.
+ * A subsequence of a string is a new string that is formed from the original string by deleting some (can be none) of the characters without disturbing the relative positions of the remaining characters.
+ * (i.e., "ace" is a subsequence of "abcde" while "aec" is not).
+ *
+ * Constraints:
+ * 0 <= s.length <= 100
+ * 0 <= t.length <= 10^4
+ * s and t consist only of lowercase English letters.
+ *
+ * Follow up:
+ * Suppose there are lots of incoming s, say s1, s2, ..., sk where k >= 109, and you want to check one by one to see if t has its subsequence.
+ * In this scenario, how would you change your code?
+ */
+
+fun main() {
+    val s = "abc"
+    val t = "ahbgdc"
+
+    val result = Solution().isSubsequence(s, t)
+
+    println(result)
+}
+
+class Solution {
+    // 시간 복잡도 : O(N)
+    // 공간 복잡도 ; O(1)
+    fun isSubsequence(s: String, t: String): Boolean {
+        var i = 0
+        var j = 0
+
+        while (i < s.length && j < t.length) {
+            if (s[i] == t[j]) {
+                i++
+            }
+
+            j ++
+        }
+
+        return i == s.length
+    }
+}