Create Substrings of Size Three with Distinct Characters.java

varunu28 · web-flow · commit 40e677eb127f · 2021-05-29T15:07:02.000-07:00
diff --git a/Easy/Substrings of Size Three with Distinct Characters.java b/Easy/Substrings of Size Three with Distinct Characters.java
@@ -0,0 +1,20 @@
+class Solution {
+  public int countGoodSubstrings(String s) {
+    Map<Character, Integer> map = new HashMap<>();
+    int count = 0;
+    for (int i = 0; i < Math.min(s.length(), 2); i++) {
+      map.put(s.charAt(i), map.getOrDefault(s.charAt(i), 0) + 1);
+    }
+    for (int i = 2; i < s.length(); i++) {
+      map.put(s.charAt(i), map.getOrDefault(s.charAt(i), 0) + 1);
+      if (map.size() == 3) {
+        count++;
+      }
+      map.put(s.charAt(i - 2), map.getOrDefault(s.charAt(i - 2), 0) - 1);
+      if (map.get(s.charAt(i - 2)) == 0) {
+        map.remove(s.charAt(i - 2));
+      }
+    }
+    return count;
+  }
+}
