Problem:
Score : 400 points

Problem Statement

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.

Output

Print the resulting string.

Sample Input 1

a
4
2 1 p
1
2 2 c
1

Sample 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.

Sample Input 2

a
6
2 2 a
2 1 b
1
2 2 c
1
1

Sample 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.

Sample Input 3

y
1
2 1 x

Sample Output 3

xy

Solution in Rust (1.15.1) (judge verdict: Accepted)

use std::collections::VecDeque;                                                                                                                     
                                                                                                                                                    
fn string_formation() -> Result<String, &'static str> {                                                                                             
    let mut S = String::new();                                                                                                                      
    std::io::stdin().read_line(&mut S)                                                                                                              
        .map_err(|_| "input error")?;                                                                                                               
    let S = S.trim_right();                                                                                                                         
                                                                                                                                                    
    let mut Q = String::new();                                                                                                                      
    std::io::stdin().read_line(&mut Q)                                                                                                              
        .map_err(|_| "input error")?;                                                                                                               
    let Q: i64 = Q.trim_right().parse::<i64>()                                                                                                      
        .map_err(|_| "parse error")?;                                                                                                               
                                                                                                                                                    
    let mut end_add = true;                                                                                                                         
    let mut queue: VecDeque<char> = VecDeque::new();                                                                                                
    for c in S.chars() {                                                                                                                            
        queue.push_back(c);                                                                                                                         
    }                                                                                                                                               
    for i in 0..Q {                                                                                                                                 
        let mut input = String::new();                                                                                                              
        std::io::stdin().read_line(&mut input)                                                                                                      
            .map_err(|_| "input error")?;                                                                                                           
        let line: Vec<char> = input.chars().collect();                                                                                              
                                                                                                                                                    
        if line[0] == '1' {                                                                                                                         
            end_add = !end_add;                                                                                                                     
        }                                                                                                                                           
        else {                                                                                                                                      
            if end_add {                                                                                                                            
                if line[2] == '1' {                                                                                                                 
                    queue.push_front(line[4]);                                                                                                      
                }                                                                                                                                   
                else {                                                                                                                              
                    queue.push_back(line[4]);                                                                                                       
                }                                                                                                                                   
            }                                                                                                                                       
            else {                                                                                                                                  
                if line[2] == '1' {
                    queue.push_back(line[4]);
                }
                else {
                    queue.push_front(line[4]);
                }
            }
        }
    }
    if end_add {
        for c in queue {
            print!("{}", c);
        }
    }
    else {
        for c in queue.iter().rev() { 
            print!("{}", c);
        }
    }
    Ok(String::from(""))
}

fn main() {
    println!("{}", string_formation().unwrap());
}