Create 0514-freedom-trail.java

Author: sujal-goswami

Diff for: java/0514-freedom-trail.java

@@ -0,0 +1,27 @@
+class Solution {
+    Map<String, Integer> cache = new HashMap<>();
+
+    public int findRotateSteps(String ring, String key) {
+        return helper(ring, key, 0, 0);
+    }
+
+    private int helper(String ring, String key, int r, int k) {
+        if (k == key.length())
+            return 0;
+        String keyCache = r + "," + k;
+        if (cache.containsKey(keyCache))
+            return cache.get(keyCache);
+
+        int res = Integer.MAX_VALUE;
+        for (int i = 0; i < ring.length(); i++) {
+            if (ring.charAt(i) == key.charAt(k)) {
+                int minDist = Math.min(Math.abs(r - i), ring.length() - Math.abs(r - i));
+                int steps = minDist + 1 + helper(ring, key, i, k + 1);
+                res = Math.min(res, steps);
+            }
+        }
+
+        cache.put(keyCache, res);
+        return res;
+    }
+}