Merge pull request #3331 from ACeldo1/2707-extra-characters-in-a-string

Create 2707-extra-characters-in-a-string.java

Author: MHamiid

java/2707-extra-characters-in-a-string.java

@@ -0,0 +1,26 @@
+/*
+    Let N = length of string s, M = length of dictionary
+    Time: O(N * M)
+    Space: O(N)
+*/
+class Solution {
+    public int minExtraChar(String s, String[] dictionary) {
+        int n = s.length();
+        int[] dp = new int[n+1];
+        
+        Arrays.fill(dp, n);
+        dp[0] = 0;
+        
+        for (int i = 1; i <= n; ++i) {
+            for (int j = 0; j < dictionary.length; ++j) {
+                int len = dictionary[j].length();
+                if (i >= len && s.substring(i - len, i).equals(dictionary[j])) {
+                    dp[i] = Math.min(dp[i], dp[i - len]);
+                }
+            }
+            dp[i] = Math.min(dp[i], dp[i - 1] + 1);
+        }
+
+        return dp[n];
+    }
+}