Description

In this problem, you need to finish a string calculator.

The calculator has four string operators:

• a + b: Concatenate the string b after the string a.
• a - b: If string b has appeared in string a, delete the first appearance of b in a, otherwise output "error".
• a / b: The number of occurrences of string b in string a.
• a @ b₁_b₂_b₃_...b_k: For all strings b_i concatenated with _, if a has appeared in string b_i, add b_i to a list, output the list in this order:
  • ​If |x| > |y|: x is listed before y
  • If |x| = |y|: follows the dictionary order

Input

The first line contains an integer N

The following N lines, each line contains an operation.

testcase:

(2/12) 0 < N < 100, 0 < |a|, |b| <= 10, only "+" operation

(3/12) 0 < N < 100, 0 < |a|, |b| <= 10, only "-" operation

(3/12) 0 < N < 100, 0 < |a|, |b| <= 10, only "/" operation

(2/12) 0 < N < 100, 0 < |a|, |b_i| <= 10, 0 < k <= 500 , only "@" operation

(2/12) 0 < N < 100, 0 < |a|, |b_i| <= 10, 0 < k <= 10000 , only "@" operation

Output

The output contains N lines, output the calculated result.

Sample Input  Download

Sample Output  Download

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