【HDU】1754 I Hate It

线段树：

 1 #include<cstdio>

 2 #define INF 987654321

 3 #define MAXN 200010

 4 int tree[MAXN << 2];

 5 inline int MAX(int x, int y) {

 6     return x > y ? x : y;

 7 }

 8 inline void PushUp(int rt) {

 9     tree[rt] = MAX(tree[rt << 1], tree[rt << 1 | 1]);

10 }

11 void Build(int L, int R, int rt) {

12     if (L == R)

13         scanf("%d", &tree[rt]);

14     else {

15         int mid = (L + R) >> 1;

16         Build(L, mid, rt << 1);

17         Build(mid + 1, R, rt << 1 | 1);

18         PushUp(rt);

19     }

20 }

21 void Update(int x, int val, int L, int R, int rt) {

22     if (L == R)

23         tree[rt] = val;

24     else {

25         int mid;

26         mid = (L + R) >> 1;

27         if (mid >= x)

28             Update(x, val, L, mid, rt << 1);

29         else

30             Update(x, val, mid + 1, R, rt << 1 | 1);

31         PushUp(rt);

32     }

33 }

34 int Query(int x, int y, int L, int R, int rt) {

35     if (x <= L && R <= y)

36         return tree[rt];

37     int ans, mid;

38     ans = -INF;

39     mid = (L + R) >> 1;

40     if (x <= mid)

41         ans = MAX(ans, Query(x, y, L, mid, rt << 1));

42     if (y > mid)

43         ans = MAX(ans, Query(x, y, mid + 1, R, rt << 1 | 1));

44     return ans;

45 }

46 int main() {

47     int n, m, x, y;

48     char ch;

49     while (~scanf("%d%d", &n, &m)) {

50         Build(1, n, 1);

51         while (m--) {

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

53             if (ch == 'Q')

54                 printf("%d\n", Query(x, y, 1, n, 1));

55             else

56                 Update(x, y, 1, n, 1);

57         }

58     }

59     return 0;

60 }

 

Splay：

 1 #include<cstdio>

 2 #include<algorithm>

 3 #define INF 987654321

 4 #define MAXN 300000

 5 using namespace std;

 6 struct SplayTree {

 7     int root;

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

 9     inline void PushUp(int x) {

10         res[x] = max(res[next[x][0]], res[next[x][1]]);

11         res[x] = max(res[x], key[x]);

12     }

13     void NewNode(int val, int x) {

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

15         key[x] = res[x] = val;

16         pre[x] = x - 1;

17         next[x - 1][1] = x;

18     }

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

20         int y, z;

21         y = pre[x];

22         z = pre[y];

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

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

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

26         pre[x] = z;

27         next[x][kind] = y;

28         pre[y] = x;

29         PushUp(y);

30         PushUp(x);

31     }

32     void Splay(int x, int goal) {

33         if (x != goal) {

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

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

36                     Rotate(x, 1);

37                 else

38                     Rotate(x, 0);

39             }

40             if (!goal)

41                 root = x;

42         }

43     }

44     void Update(int x, int val) {

45         x++;

46         Splay(x, 0);

47         key[x] = val;

48         PushUp(x);

49     }

50     void Query(int x, int y) {

51         y += 2;

52         Splay(x, 0);

53         Splay(y, x);

54         printf("%d\n", res[next[y][0]]);

55     }

56 } tree;

57 int main() {

58     char ch;

59     int n, q;

60     int i, x, y;

61     while (~scanf("%d%d", &n, &q)) {

62         tree.NewNode(-INF, 1);

63         for (i = 0; i < n; i++) {

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

65             tree.NewNode(x, i + 2);

66         }

67         tree.NewNode(-INF, n + 2);

68         for (i = n + 2; i; i--)

69             tree.PushUp(i);

70         tree.root = 1;

71         while (q--) {

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

73             if (ch == 'Q')

74                 tree.Query(x, y);

75             else

76                 tree.Update(x, y);

77         }

78     }

79     return 0;

80 }