Create Count Complete Substrings.java

Author: varunu28

Medium/Count Complete Substrings.java

@@ -0,0 +1,54 @@
+class Solution {
+    public int countCompleteSubstrings(String word, int k) {
+        int count = 0;
+        StringBuilder sb = new StringBuilder();
+        int n = word.length();
+        for (int i = 0; i < n; i++) {
+            sb.append(word.charAt(i));
+            if (i < n - 1 && Math.abs(word.charAt(i) - word.charAt(i + 1)) > 2) {
+                count += calculateSubstrings(sb.toString(), k);
+                sb.setLength(0);
+            }
+        }
+        count += calculateSubstrings(sb.toString(), k);
+        return count;
+    }
+
+    private int calculateSubstrings(String s, int k) {
+        int count = 0;
+        int n = s.length();
+        for (int i = 1; i <= 26; i++) {
+            int len = k * i;
+            int[] freq = new int[26];
+            if (len > n) {
+                break;
+            }
+            for (int j = 0; j < len; j++) {
+                freq[s.charAt(j) - 'a']++;
+            }
+            if (check(freq, i, k)) {
+                count++;
+            }
+            for (int j = len; j < n; j++) {
+                freq[s.charAt(j - len) - 'a']--;
+                freq[s.charAt(j) - 'a']++;
+                if (check(freq, i, k)) {
+                    count++;
+                }
+            }
+        }
+        return count;
+    }
+
+    private boolean check(int[] freq, int i, int k) {
+        for (int value : freq) {
+            if (value == 0) {
+                continue;
+            }
+            if (value != k) {
+                return false;
+            }
+        }
+        return true;
+    }
+}