Revert "rearrange the dictionary"

This reverts commit 975a7a1.

Author: zhaoguanchen

Java/src/leetcode/solution/DataStruct/Solution.java

@@ -0,0 +1,49 @@
+package leetcode.solution.stack;
+
+import java.util.Stack;
+
+/**
+ * 394. Decode String
+ */
+public class DecodeString {
+
+    public static void main(String[] args) {
+        String s = "3[a]2[bc]";
+        DecodeString decodeString = new DecodeString();
+        System.out.println(decodeString.decodeString(s));
+        // Output: "aaabcbc"
+    }
+
+    public String decodeString(String s) {
+        Stack<StringBuilder> charStack = new Stack<>();
+        Stack<Integer> countStack = new Stack<>();
+        StringBuilder current = new StringBuilder();
+
+        int k = 0;
+        for (int i = 0; i < s.length(); i++) {
+            char ch = s.charAt(i);
+            if (Character.isDigit(ch)) {
+                k = k * 10 + ch - '0';
+            } else if (Character.isLetter(ch)) {
+                current.append(ch);
+            } else if ('[' == ch) {
+                countStack.push(k);
+                k = 0;
+                charStack.push(current);
+                current = new StringBuilder();
+            } else if (']' == ch) {
+                StringBuilder encodeStr = current;
+                int times = countStack.pop();
+                StringBuilder existStr = charStack.pop();
+                for (int j = times; j > 0; j--) {
+                    existStr.append(encodeStr);
+                }
+                current = existStr;
+            }
+        }
+
+        return current.toString();
+    }
+
+
+}