【HYSBZ】1503 郁闷的出纳员

  1 #include<cstdio>

  2 #define INF 0x7FFFFFFF

  3 #define MAXN 100010

  4 struct SplayTree {

  5     int num[MAXN], next[MAXN][2], pre[MAXN], key[MAXN];

  6     int root, size;

  7     inline void PushUp(int x) {

  8         num[x] = num[next[x][0]] + num[next[x][1]] + 1;

  9     }

 10     inline void Rotate(int x, int kind) {

 11         int y, z;

 12         y = pre[x];

 13         z = pre[y];

 14         next[y][!kind] = next[x][kind];

 15         pre[next[x][kind]] = y;

 16         next[z][next[z][1] == y] = x;

 17         pre[x] = z;

 18         next[x][kind] = y;

 19         pre[y] = x;

 20         PushUp(y);

 21         PushUp(x);

 22     }

 23     void Splay(int x, int goal) {

 24         if (x != goal) {

 25             while (pre[x] != goal) {

 26                 if (next[pre[x]][0] == x)

 27                     Rotate(x, 1);

 28                 else

 29                     Rotate(x, 0);

 30             }

 31             if (!goal)

 32                 root = x;

 33         }

 34     }

 35     inline void NewNode(int &x, int y, int val) {

 36         x = ++size;

 37         num[x] = 1;

 38         pre[x] = y;

 39         next[x][0] = next[x][1] = 0;

 40         key[x] = val;

 41         next[y][val > key[y]] = x;

 42     }

 43     void Insert(int val) {

 44         int x, y;

 45         for (x = root, y = 0; x; x = next[x][val > key[x]]) {

 46             y = x;

 47             num[x]++;

 48         }

 49         NewNode(x, y, val);

 50         Splay(x, 0);

 51     }

 52     int Search(int val) {

 53         int res, x;

 54         for (res = 0, x = root; x; x = next[x][val > key[x]]) {

 55             if (key[x] >= val && key[res] >= key[x])

 56                 res = x;

 57         }

 58         return res;

 59     }

 60     int Select(int k) {

 61         int x;

 62         k = num[root] - k;

 63         for (x = root; num[next[x][0]] + 1 != k;) {

 64             if (num[next[x][0]] + 1 < k) {

 65                 k -= num[next[x][0]] + 1;

 66                 x = next[x][1];

 67             } else

 68                 x = next[x][0];

 69         }

 70         Splay(x, 0);

 71         return key[x];

 72     }

 73     inline void Init() {

 74         root = size = 0;

 75         num[0] = next[0][0] = next[0][1] = pre[0];

 76         key[0] = INF;

 77         Insert(INF);

 78     }

 79 } tree;

 80 int main() {

 81     char ch;

 82     int q, base, diff, ans, x;

 83     while (~scanf("%d%d", &q, &base)) {

 84         tree.Init();

 85         diff = ans = 0;

 86         while (q--) {

 87             scanf(" %c%d", &ch, &x);

 88             if (ch == 'I') {

 89                 if (x >= base)

 90                     tree.Insert(x - base + diff);

 91             } else if (ch == 'A')

 92                 diff -= x;

 93             else if (ch == 'S') {

 94                 diff += x;

 95                 tree.Splay(tree.Search(diff), 0);

 96                 ans += tree.num[tree.next[tree.root][0]];

 97                 tree.num[tree.root] -= tree.num[tree.next[tree.root][0]];

 98                 tree.next[tree.root][0] = 0;

 99             } else {

100                 if (x >= tree.num[tree.root])

101                     puts("-1");

102                 else

103                     printf("%d\n", tree.Select(x) + base - diff);

104             }

105         }

106         printf("%d\n", ans);

107     }

108     return 0;

109 }