def main():
    x = input().split(' ')
    for i in range(len(x)-1, -1, -1):
        if x[i] == 'f':
            x[i] = x[i+1] * 2 - 3
            del x[i+1:i+2]
            continue
        if x[i] == 'g':
            x[i] = x[i+1] * 2 + x[i+2] - 7
            del x[i+1:i+3]
            continue
        if x[i] == 'h':
            x[i] = x[i+1] * 3 - x[i+2] * 2 + x[i+3]
            del x[i+1:i+4]
            continue
        x[i] = int(x[i])
    print(x[0])
main()