1 #include <cstdio>
 2 #include <cstring>
 3 #define lson l, m, rt << 1
 4 #define rson m + 1, r, rt << 1 | 1
 5
 6 const int MAX_N = 500000 + 10;
 7 int sum[MAX_N << 2];
 8
 9 void pushup(int rt)
10 {
11     if (rt >> 1 % 5 == 3)
12         sum[rt] += sum[rt >> 1];
13     if (rt >>1 | 1 % 5 == 3)
14         sum[rt] += sum[rt >> 1 | 1];
15 }
16
17 void build(int l, int r, int rt)
18 {
19     sum[rt] = r - l + 1;
20     if (l == r)
21     {
22         return ;
23     }
24     int m = (l + r) >> 1;
25     build (lson);
26     build (rson);
27     pushup (rt);
28 }
29
30 void update(int p, int l, int r, int rt)
31 {
32     if (l == r)
33     {
34         sum[rt] = p;
35         return ;
36     }
37     int m = (l + r) >> 1;
38     if (p <= m)    update (p, lson);
39     else    update (p, rson);
40
41     pushup (rt);
42 }
43
44
45 int main(void)        //HDOJ 4288 Coder
46 {
47     //freopen ("inG.txt", "r", stdin);
48     int n;
49     char op[10];
50     int x;
51
52     while (~scanf ("%d", &n))
53     {
54         build (1, n, 1);
55         while (n--)
56         {
57             scanf ("%s", &op);
58             if (strcmp (op, "add") == 0)
59             {
60                 scanf ("%d", &x);
61                 update (x, 1, n, 1);
62             }
63             if (strcmp (op, "del") == 0)
64             {
65                 scanf ("%d", &x);
66                 update (-x, 1, n, 1);
67             }
68             if (strcmp (op, "sum") == 0)
69             {
70                 printf ("%d\n", sum[1]);
71             }
72         }
73     }
74
75     return 0;
76 }