Problem was to implement stack using two queue.
We need to perform basic operations like push,pop,top,empty.
Primary queue was q1.

for push(),empty() and top() I used only one queue(q1)

push()

• whenever a new item was pushed, it was added to q1.

void push(int x) {
        q1.push(x);
    }

empty()

• For empty I just check it q1 was empty or not.

bool empty() {
        return q1.empty();
    }

top()

• return q1.back()

int top() {
        return q1.back();     
    }

pop()

• I created one more queue and moved everything from q1 to q2 leaving the last element.
• then I stored the last element in a variable x, deleted it from q1.
• now q1 is empty and q2 has all remaining elements.
• then I simply copied back everything from q2 to q1.
• return x.

int pop() {
        queue<int> q2;                      //creating q1
        int  x;
        while(q1.size()!=1){                // moved everything from q1 to q2 leaving the last element.
             x=q1.front();
            q1.pop();
            q2.push(x);
        }
         x=q1.front();                      //storing and deleting last element from q1
        q1.pop();
        q1=q2;                              //coping everything from q2 to q1
        return x;                            //returning x
    }

LInk to my code

Time complexity:

• push- O(n)
• top- O(1)
• empty- O(1)
• pop- O(n) and space complexity - O(n)

I hope you will find my solution helpful!😊