input = open('input.txt', 'r').read().splitlines()

nums = []

current_num = ''

for line in input:
    if current_num != '':
        if column_index > len(nums) - 1:
            nums.append([current_num])
        else:
            nums[column_index].append(current_num)
    current_num = ''
    column_index = 0
    for char in line:
        if char == ' ':
            if current_num != '':
                if column_index > len(nums) - 1:
                    nums.append([current_num])
                    column_index += 1
                else:
                    nums[column_index].append(current_num)
                    column_index += 1
                current_num = ''
        else:
            current_num += char

answer = 0

for column in nums:
    column_combo = 0
    if column[-1] == '+':
        for num in column[:-1]:
            column_combo += int(num)
        answer += column_combo
    elif column[-1] == '*':
        for num in column[:-1]:
            if column_combo == 0:
                column_combo += int(num)
            else:
                column_combo *= int(num)
        answer += column_combo

print(answer)