Question

Suppose we execute the following stack operations on a stack of ints.

push(1);
pop(); // #1
push(10);
pop(); // #2
push(7);
push(4);
push(3);
pop(); // #3
push(5);
pop(); //#4

Write the final state of the stack, and for each pop() operation, write the value that will be popped off the stack (pops are numbered so you can refer to them).

Answer 1

push(1);
stack: [1]

pop(); // #1
Popped value 1
stack: []

push(10);
stack: [10]

pop(); // #2
Popped value 10
stack: []

push(7);
stack: [7]

push(4);
stack: [7, 4]

push(3);
stack: [7, 4, 3]

pop(); // #3
Popped value 3
stack: [7, 4]

push(5);
stack: [7, 4, 5]

pop(); //#4
Popped value 5
stack: [7, 4]

Final stack: [7, 4]