#!/bin/bash
a=0
b=0

function num() {
	echo $2 # could have used awk, but this works ;p
}

while read line; do
	x=$(num $line)
	if [[ "$line" == "forward"* ]]; then
		a=$((a+x))
	elif [[ "$line" == "up"* ]]; then
		b=$((b-x))
	elif [[ "$line" == "down"* ]]; then
		b=$((b+x))
	fi
done


echo $((b*a))