первая нахуй

n = int(input())

s = list()
rev = dict()
for i in range(n):
    inp = list(input().split())

    if inp[0] == 'add':
        cars = int(inp[1])
        good = inp[2]

        s.append((cars, good))

        if good in rev.keys():
            rev[good] += cars
        else:
            rev[good] = cars
    elif inp[0] == 'delete':
        cars = int(inp[1])
        while cars != 0:
            curr_cars, curr_good = s[len(s) - 1]

            if curr_cars <= cars:
                s.pop()
                cars -= curr_cars
                rev[curr_good] -= curr_cars
            else:
                s.pop()
                rev[curr_good] -= cars
                s.append((curr_cars - cars, curr_good))
                cars = 0
    else:
        good = inp[1]
        if good in rev.keys():
            print(rev[good])
        else:
            print(0)