typescript boilerplate:

`use strict";

process.stdin.resume(); process.stdin.setEncoding("utf-8"); let inputString: string = ""; let inputLines: string[] = []; let currentLine: number = 0; process.stdin.on("data", function (inputStdin: string): void { inputString += inputStdin; });

process.stdin.on("end", function (): void { inputLines = inputString.split("\n"); inputString = ""; main(); });

function readLine(): string { return inputLines[currentLine++]; }

class stackQueue { private s1: number[] = []; private s2: number[] = [];

constructor() { this.s1 = []; this.s2 = []; }

enqueue(x: number) { // Enter your code here }

dequeue() { // Enter your code here }

print() { // Enter your code here } }

function main() { const testQueue = new stackQueue(); const commandMap = { "1": "enqueue", "2": "dequeue", "3": "print" } as const;

inputLines.shift();

inputLines.map((inputLine: string) => { const [command, input] = inputLine.split(" ") as ["1" | "2" | "3", string]; const method = commandMap[command]; if (method == "enqueue") { return testQueue.enqueue(Number(input)); } return testQueuemethod; }); }

`

javascript boilerplate "use strict";

process.stdin.resume(); process.stdin.setEncoding("utf-8"); let inputString = ""; let inputLines = []; let currentLine = 0; process.stdin.on("data", function (inputStdin) { inputString += inputStdin; });

process.stdin.on("end", function () { inputLines = inputString.split("\n"); inputString = ""; main(); });

function readLine() { return inputLines[currentLine++]; }

class stackQueue { constructor() { this.s1 = []; this.s2 = []; }

enqueue(x) { // Enter your code here }

dequeue() { // Enter your code here }

print() { // Enter your code here } }

function main() { const testQueue = new stackQueue(); const commandMap = { 1: "enqueue", 2: "dequeue", 3: "print" };

inputLines.shift();

inputLines.map((inputLine) => { const [command, input] = inputLine.split(" "); const method = commandMap[command]; if (method == "enqueue") { return testQueue.enqueue(Number(input)); } return testQueuemethod; }); }

`

Java solution

public class Solution { private Stack stackEnqueue = new Stack<>(); private Stack stackDequeue = new Stack<>();

// Enqueue
public void enqueue(int n){
    stackEnqueue.push(n);
}

// Dequeue
public void dequeue(){
    reverseStack();
    if(!stackDequeue.isEmpty()){
        stackDequeue.pop();
    }
}

//Reverse
private void reverseStack(){
    if(stackDequeue.isEmpty()){
        while(!stackEnqueue.isEmpty()){
            stackDequeue.push(stackEnqueue.pop());
        }
    }
}

//Print front element
public void printFrontElement(){
    reverseStack();
    if(!stackDequeue.isEmpty()){
        System.out.println(stackDequeue.peek());
    }
}
public static void main(String[] args) {
    /* Enter your code here. Read input from STDIN. Print output to STDOUT. Your class should be named Solution. */
    Scanner scanner = new Scanner((System.in));
    Solution twoStackQueue = new Solution();
    int count = scanner.nextInt();
    for(int i = 0; i< count; i++){
        int choice = scanner.nextInt();
        switch (choice){
            case 1:
                int enqueueNumber = scanner.nextInt();
                twoStackQueue.enqueue(enqueueNumber);
                break;
            case 2:
                twoStackQueue.dequeue();
                break;
            case 3:
                twoStackQueue.printFrontElement();
                break;
        }
    }
    scanner.close();
}

}

Using Python3

old, new = [], []
for _ in range(int(input())):
    val = list(map(int,input().split()))
    if val[0] == 1:
        new.append(val[1])
    elif val[0] == 2:
        if not old :
            while new : old.append(new.pop())
        old.pop()
    else:
        print(old[-1] if old else new[0])

Use perl language:

It's a one liner code.

while(<>){(v)=split;v:c==3&&print"$q[0]\n"}