from typing import List, Tuple, Optional
from collections import deque, Counter
from queue import PriorityQueue
import math
from functools import lru_cache
import random
import copy
import sys
sys.setrecursionlimit(9999)
MOD = 10**9 + 7
init_a = int(input())
s = input()
n = len(s)
i = 0
ss = ""
while i < n:
if i+2 <= n-1 and (s[i:i+3] == 'a++' or s[i:i+3] == '++a'):
ss += "X" if s[i:i+3] == 'a++' else 'Y'
i += 3
else:
ss += s[i]
i += 1
if ss[0] != '-':
ss = '+' + ss
arr = []
f = []
n = len(ss)
i = 0
while i < n:
j = i
while j+1 < n and (ss[j+1] != 'X' and ss[j+1] != 'Y'):
j += 1
if ss[j] == '*':
v = int(ss[i: j])
arr.append((v, ss[j+1]))
else:
if ss[i] == '-':
arr.append((-1, ss[j+1]))
else:
arr.append((1, ss[j+1]))
i = j+2
arr.sort()
a = init_a
tot = 0
for v, ch in arr:
if ch == 'Y':
a += 1
tot += a * v
if ch == 'X':
a += 1
print(tot)
1701A - Grass Field | 489C - Given Length and Sum of Digits |
886B - Vlad and Cafes | 915A - Garden |
356A - Knight Tournament | 1330A - Dreamoon and Ranking Collection |
1692B - All Distinct | 1156C - Match Points |
1675A - Food for Animals | 1328C - Ternary XOR |
1689A - Lex String | 1708B - Difference of GCDs |
863A - Quasi-palindrome | 1478A - Nezzar and Colorful Balls |
1581B - Diameter of Graph | 404A - Valera and X |
908A - New Year and Counting Cards | 146A - Lucky Ticket |
1594C - Make Them Equal | 1676A - Lucky |
1700B - Palindromic Numbers | 702C - Cellular Network |
1672C - Unequal Array | 1706C - Qpwoeirut And The City |
1697A - Parkway Walk | 1505B - DMCA |
478B - Random Teams | 1705C - Mark and His Unfinished Essay |
1401C - Mere Array | 1613B - Absent Remainder |