String Formation

AtCoder

IDabc158_d

Time2000ms

Memory256MB

Difficulty—

Takahashi has a string $S$ consisting of lowercase English letters. Starting with this string, he will produce a new one in the procedure given as follows. The procedure consists of $Q$ operations. In Operation $i$ $(1 \leq i \leq Q)$, an integer $T_i$ is provided, which means the following: * If $T_i = 1$: reverse the string $S$. * If $T_i = 2$: An integer $F_i$ and a lowercase English letter $C_i$ are additionally provided. * If $F_i = 1$ : Add $C_i$ to the beginning of the string $S$. * If $F_i = 2$ : Add $C_i$ to the end of the string $S$. Help Takahashi by finding the final string that results from the procedure. ## Constraints * $1 \leq |S| \leq 10^5$ * $S$ consists of lowercase English letters. * $1 \leq Q \leq 2 \times 10^5$ * $T_i = 1$ or $2$. * $F_i = 1$ or $2$, if provided. * $C_i$ is a lowercase English letter, if provided. ## Input Input is given from Standard Input in the following format: $S$ $Q$ $Query_1$ $:$ $Query_Q$ In the $3$\-rd through the $(Q+2)$\-th lines, $Query_i$ is one of the following: $1$ which means $T_i = 1$, and: $2$ $F_i$ $C_i$ which means $T_i = 2$. [samples]

Samples

Input #1

Output #1

cpa

There will be $Q = 4$ operations. Initially, $S$ is `a`.

*   Operation $1$: Add `p` at the beginning of $S$. $S$ becomes `pa`.
    
*   Operation $2$: Reverse $S$. $S$ becomes `ap`.
    
*   Operation $3$: Add `c` at the end of $S$. $S$ becomes `apc`.
    
*   Operation $4$: Reverse $S$. $S$ becomes `cpa`.
    

Thus, the resulting string is `cpa`.

Input #2

Output #2

aabc

There will be $Q = 6$ operations. Initially, $S$ is `a`.

*   Operation $1$: $S$ becomes `aa`.
    
*   Operation $2$: $S$ becomes `baa`.
    
*   Operation $3$: $S$ becomes `aab`.
    
*   Operation $4$: $S$ becomes `aabc`.
    
*   Operation $5$: $S$ becomes `cbaa`.
    
*   Operation $6$: $S$ becomes `aabc`.
    

Thus, the resulting string is `aabc`.

Input #3

y
1
2 1 x

Output #3

xy

API Response (JSON)

{
  "problem": {
    "name": "String Formation",
    "description": {
      "content": "Takahashi has a string $S$ consisting of lowercase English letters. Starting with this string, he will produce a new one in the procedure given as follows. The procedure consists of $Q$ operations. In",
      "description_type": "Markdown"
    },
    "platform": "AtCoder",
    "limit": {
      "time_limit": 2000,
      "memory_limit": 262144
    },
    "difficulty": "None",
    "is_remote": true,
    "is_sync": true,
    "sync_url": null,
    "sign": "abc158_d"
  },
  "statements": [
    {
      "statement_type": "Markdown",
      "content": "Takahashi has a string $S$ consisting of lowercase English letters.\nStarting with this string, he will produce a new one in the procedure given as follows.\nThe procedure consists of $Q$ operations. In...",
      "is_translate": false,
      "language": "English"
    }
  ]
}

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