stack_with_max

# Input
q = int(input())

# Init
st1 = [-1]
stm = [-1]
res = ''

# Main
for i in range(q):
    op = input().rstrip()
    if ' ' in op:
        op = op.split()
        val = int(op[1])
        st1.append(val)
        if val > stm[len(stm)-1]:
            stm.append(val)
        else:
            stm.append(stm[len(stm)-1])
    elif op == 'pop':
        st1.pop()
        stm.pop()
    else:
        res = stm[len(stm)-1]
        # Output
        print(res)