Create 1143-Longest-Common-Subsequence.java

java/1143-Longest-Common-Subsequence.java

@@ -0,0 +1,19 @@
+//memoized version
+
+class Solution {
+ public int longestCommonSubsequence(String text1, String text2) {
+ int[][] dp = new int[text1.length()][text2.length()];
+ return LCS(text1, text2, 0, 0, dp);
+ }
+
+ public int LCS(String s1, String s2, int i, int j, int[][] dp) {
+ if (i>=s1.length() || j>=s2.length()) return 0;
+ else if (dp[i][j]!=0) return dp[i][j];
+ else if (s1.charAt(i) == s2.charAt(j)) return 1+LCS(s1, s2, i+1, j+1, dp);
+ else{ 
+ dp[i][j] = Math.max(LCS(s1, s2, i+1, j, dp), LCS(s1, s2, i, j+1, dp));
+ return dp[i][j];
+ }
+ }
+
+}