H. Stack

• Time : $O(|s|)$
• Space : $O(|s|)$

set [0] 10
co x {
    cin [1]
    eq [3] [1] 10
    if [3] ac
    eq [3] [1] 42
    if [3] sub [2] [0] 1
    if [3] mul [[2]] [[2]] [[0]]
    if [3] dec [0]
    eq [4] [1] 43
    if [4] sub [2] [0] 1
    if [4] add [[2]] [[2]] [[0]]
    if [4] dec [0]
    add [4] [4] [3]
    sub [4] 1 [4]
    if [4] inc [0]
    if [4] sub [[0]] [1] 48
}
ca x
iout [[0]]
ac