Added Maximum Number of Vowels in a Substring of Given Length.java

varunu28 · varunu28 · commit f977fa6394e8 · 2020-05-25T18:59:12.000-05:00
diff --git a/Medium/Maximum Number of Vowels in a Substring of Given Length.java b/Medium/Maximum Number of Vowels in a Substring of Given Length.java
@@ -0,0 +1,32 @@
+class Solution {
+  public int maxVowels(String s, int k) {
+    Map<Character, Integer> map = new HashMap<>();
+    String vowels = "aeiou";
+    int count = 0;
+    int maxCount = 0;
+    int start = 0;
+    int end = 0;
+    int n = s.length();
+    while (end < (k - 1)) {
+      if (vowels.indexOf(s.charAt(end)) != -1) {
+        map.put(s.charAt(end), map.getOrDefault(s.charAt(end), 0) + 1);
+        count++;
+      }
+      end++;
+    }
+    while (end < n) {
+       if (vowels.indexOf(s.charAt(end)) != -1) {
+        map.put(s.charAt(end), map.getOrDefault(s.charAt(end), 0) + 1);
+         count++;
+      }
+      end++;
+      maxCount = Math.max(maxCount, count);
+      if (vowels.indexOf(s.charAt(start)) != -1) {
+        map.put(s.charAt(start), map.getOrDefault(s.charAt(start), 0) - 1);
+        count--;
+      }
+      start++;
+    }
+    return maxCount;
+  }
+}
