update 424 java

yennanliu · Mar 14, 2024 · 07bc7ea · 07bc7ea
1 parent 3374619
commit 07bc7ea
Showing 1 changed file with 33 additions and 3 deletions.
diff --git a/leetcode_java/src/main/java/LeetCodeJava/HashTable/LongestRepeatingCharacterReplacement.java b/leetcode_java/src/main/java/LeetCodeJava/HashTable/LongestRepeatingCharacterReplacement.java
@@ -9,9 +9,39 @@
 public class LongestRepeatingCharacterReplacement {
 
     // V0
-    // IDEA : TWO POINTER + HASHMAP (modified by GPT)
+    // IDEA : TWO POINTER + HASHMAP + FOR LOOP
     // https://github.com/yennanliu/CS_basics/blob/master/leetcode_python/Hash_table/longest-repeating-character-replacement.py
     public int characterReplacement(String s, int k) {
+        Map<Character, Integer> table = new HashMap<>();
+        int res = 0;
+        int p1 = 0;
+
+        for (int p2 = 0; p2 < s.length(); p2++) {
+            char c = s.charAt(p2);
+            table.put(c, table.getOrDefault(c, 0) + 1);
+
+            while ( (p2 - p1 + 1) - getMaxValue(table) > k) {
+                char c1 = s.charAt(p1);
+                table.put(c1, table.get(c1) - 1);
+                p1++;
+            }
+            res = Math.max(res, p2 - p1 + 1);
+        }
+        return res;
+    }
+
+    private int getMaxValue(Map<Character, Integer> map) {
+        int max = 0;
+        for (int value : map.values()) {
+            max = Math.max(max, value);
+        }
+        return max;
+    }
+
+    // V0'
+    // IDEA : TWO POINTER + HASHMAP (modified by GPT)
+    // https://github.com/yennanliu/CS_basics/blob/master/leetcode_python/Hash_table/longest-repeating-character-replacement.py
+    public int characterReplacement_0(String s, int k) {
         Map<Character, Integer> table = new HashMap<>();
         int res = 0;
         int p1 = 0, p2 = 0;
@@ -21,7 +51,7 @@ public int characterReplacement(String s, int k) {
             table.put(c, table.getOrDefault(c, 0) + 1);
             p2++;
 
-            while (p2 - p1 - getMaxValue(table) > k) {
+            while (p2 - p1 - getMaxValue_0(table) > k) {
                 char c1 = s.charAt(p1);
                 table.put(c1, table.get(c1) - 1);
                 p1++;
@@ -31,7 +61,7 @@ public int characterReplacement(String s, int k) {
         return res;
     }
 
-    private int getMaxValue(Map<Character, Integer> map) {
+    private int getMaxValue_0(Map<Character, Integer> map) {
         int max = 0;
         for (int value : map.values()) {
             max = Math.max(max, value);