#!/usr/bin/env python

Q = int(input())
events = []
for i in range(Q):
    events.append([int(x) for x in input().split()])

labo_indexs = {}
for (i, event) in enumerate(events):
    if event[0] == 1:
        labo_indexs[i+1] = event[1]
    elif event[0] == 2:
        del labo_indexs[event[1]]
    elif event[0] == 3:
        labo_indexs = dict([(x, y+event[1]) for (x, y) in labo_indexs.items()])

    vals = labo_indexs.values()
    for l in range(len(vals), -1, -1):
        if len([x for x in vals if x >= l]) >= l:
            print(l)
            break
        else:
            continue