【HYSBZ】1588 营业额统计

数据有两组漏了一个数，所以在读入之前要先赋值为0。

 1 #include<cstdio>

 2 #include<algorithm>

 3 #define MAXN 100010

 4 #define INF 0x7FFFFFFF

 5 using namespace std;

 6 struct SpalyTree {

 7     int size, root;

 8     int next[MAXN][2], pre[MAXN], key[MAXN];

 9     void Init() {

10         size = root = 0;

11     }

12     void NewNode(int &rt, int father, int val) {

13         rt = ++size;

14         next[rt][0] = next[rt][1] = 0;

15         pre[rt] = father;

16         key[rt] = val;

17     }

18     void Rotate(int x, int kind) {

19         int y = pre[x];

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

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

22         if (pre[y])

23             next[pre[y]][next[pre[y]][1] == y] = x;

24         pre[x] = pre[y];

25         next[x][kind] = y;

26         pre[y] = x;

27     }

28     void Splay(int x, int goal) {

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

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

31                 Rotate(x, 1);

32             else

33                 Rotate(x, 0);

34         }

35         if (!goal)

36             root = x;

37     }

38     bool Insert(int k) {

39         int x, y;

40         for (x = root; next[x][k > key[x]]; x = next[x][k > key[x]]) {

41             if (k == key[x]) {

42                 Splay(x, 0);

43                 return false;

44             }

45         }

46         NewNode(next[x][k > key[x]], x, k);

47         Splay(next[x][k > key[x]], 0);

48         return true;

49     }

50     int GetPre() {

51         int x = next[root][0];

52         if (x) {

53             while (next[x][1])

54                 x = next[x][1];

55             return key[x];

56         }

57         return INF;

58     }

59     int GetNext() {

60         int x = next[root][1];

61         if (x) {

62             while (next[x][0])

63                 x = next[x][0];

64             return key[x];

65         }

66         return INF;

67     }

68 };

69 SpalyTree tree;

70 int main() {

71     int n, ans, x, a, b;

72     while (~scanf("%d%d", &n, &ans)) {

73         tree.Init();

74         tree.NewNode(tree.root, 0, ans);

75         while (--n) {

76             x = 0;

77             scanf("%d", &x);

78             if (tree.Insert(x)) {

79                 a = tree.GetPre();

80                 if (a < INF)

81                     a = x - a;

82                 b = tree.GetNext();

83                 if (b < INF)

84                     b -= x;

85                 ans += min(a, b);

86             }

87         }

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

89     }

90     return 0;

91 }