from os import readlink


f = open ('input2.txt', 'r')
input = f.readlines()
forward = 0
depth = 0
for i in range(len(input)):
    input[i] = input[i].strip()
for i in range(len(input)):
    direct, amount = input[i].split(" ", 1)
    if direct == 'forward':
        forward += int(amount)
    if direct == 'down':
        depth += int(amount)
    if direct == 'up':
        depth -= int(amount)
x = depth * forward
print(x)