Create Decoded String at Index.java

varunu28 · web-flow · commit c0bc4aba017f · 2023-09-27T08:34:44.000-07:00
diff --git a/Medium/Decoded String at Index.java b/Medium/Decoded String at Index.java
@@ -0,0 +1,27 @@
+class Solution {
+    public String decodeAtIndex(String s, int k) {
+        long size = 0;
+        int n = s.length();
+        for (int i = 0; i < n; i++) {
+            char c = s.charAt(i);
+            if (Character.isDigit(c)) {
+                size *= (c - '0');
+            } else {
+                size++;
+            }
+        }
+        for (int i = n - 1; i >= 0; i--) {
+            char c = s.charAt(i);
+            k %= size;
+            if (k == 0 && Character.isLetter(c)) {
+                return Character.toString(c);
+            }
+            if (Character.isDigit(c)) {
+                size /= (c - '0');
+            } else {
+                size--;
+            }
+        }
+        return "";
+    }
+}
