import sys
input = sys.stdin.readline

from heapq import heappop,heappush

N=int(input())

X=[input().split() for i in range(2*N)]

X.reverse()

l=0
r=0
ANS=0
H=[]

for s,x,y in X:
    x=int(x)
    y=int(y)

    if s==")":
        if y>=x:
            r+=1
            ANS+=y
        else:
            ANS+=x
            heappush(H,(x-y))
            l-=1
    else:
        if x>=y:
            l+=1
            ANS+=x
        else:
            ANS+=y
            heappush(H,(y-x))
            r-=1

    if l<0 or r<0:
        k=heappop(H)
        ANS-=k
        l+=1
        r+=1

print(ANS)