原题链接：http://acm.hust.edu.cn/vjudge/problem/viewProblem.action?id=18902
伸展树的区间翻转剪切。。。
如下：
1 #include<cstdio> 2 #include<cstdlib> 3 #include<iostream> 4 #include<algorithm> 5 const int Max_N = 100010; 6 struct Node{ 7 int v, s, rev; 8 Node *pre, *ch[2]; 9 inline void set(int _v = -1, int _s = 0, Node *p = NULL){ 10 v = _v, s = _s, rev = 0; 11 pre = ch[0] = ch[1] = p; 12 } 13 inline void push_up(){ 14 s = ch[0]->s + ch[1]->s + 1; 15 } 16 inline void update(){ 17 rev ^= 1; 18 std::swap(ch[0], ch[1]); 19 } 20 inline void push_down(){ 21 if (rev != 0){ 22 rev ^= 1; 23 ch[0]->update(); 24 ch[1]->update(); 25 } 26 } 27 }; 28 struct SplayTree{ 29 int N = 0; 30 Node *tail, *root, *null, stack[Max_N]; 31 void init(int n){ 32 N = n, tail = &stack[0]; 33 null = tail++; 34 null->set(); 35 root = newNode(-1); 36 root->ch[1] = newNode(-1); 37 root->ch[1]->pre = root; 38 Node *x = built(1, n); 39 root->ch[1]->ch[0] = x; 40 x->pre = root->ch[1]; 41 root->ch[1]->push_up(); 42 root->push_up(); 43 } 44 inline Node *newNode(int v){ 45 Node *p = tail++; 46 p->set(v, 1, null); 47 return p; 48 } 49 Node *built(int l, int r){ 50 if (l > r) return null; 51 int mid = (l + r) >> 1; 52 Node *p = newNode(mid); 53 p->ch[0] = built(l, mid - 1); 54 if (p->ch[0] != null) p->ch[0]->pre = p; 55 p->ch[1] = built(mid + 1, r); 56 if (p->ch[1] != null) p->ch[1]->pre = p; 57 p->push_up(); 58 return p; 59 } 60 inline void rotate(Node *x, int c){ 61 Node *y = x->pre; 62 y->push_down(), x->push_down(); 63 y->ch[!c] = x->ch[c]; 64 x->pre = y->pre; 65 if (x->ch[c] != null) x->ch[c]->pre = y; 66 if (y->pre != null) y->pre->ch[y->pre->ch[0] != y] = x; 67 x->ch[c] = y; 68 y->pre = x; 69 y->push_up(); 70 if (y == root) root = x; 71 } 72 inline void splay(Node *x, Node *f){ 73 if (x == root) return; 74 for (; x->pre != f; x->push_down()){ 75 if (x->pre->pre == f){ 76 rotate(x, x->pre->ch[0] == x); 77 } else { 78 Node *y = x->pre, *z = y->pre; 79 if (z->ch[0] == y){ 80 if (y->ch[0] == x) 81 rotate(y, 1), rotate(x, 1); 82 else rotate(x, 0), rotate(x, 1); 83 } else { 84 if (y->ch[1] == x) 85 rotate(y, 0), rotate(x, 0); 86 else rotate(x, 1), rotate(x, 0); 87 } 88 } 89 } 90 x->push_up(); 91 } 92 inline Node *select(Node *x, int k){ 93 for (int t = 0; x != null;){ 94 x->push_down(); 95 t = x->ch[0]->s; 96 if (t == k) break; 97 else if (k < t) x = x->ch[0]; 98 else k -= t + 1, x = x->ch[1]; 99 } 100 return x; 101 } 102 inline Node *get_range(int l, int r){ 103 splay(select(root, l - 1), null); 104 splay(select(root, r + 1), root); 105 return root->ch[1]->ch[0]; 106 } 107 inline Node *reverse(int l, int r){ 108 Node *x = get_range(l, r); 109 x->update(); 110 return x; 111 } 112 inline void cut_link(int l, int r){ 113 Node *x = reverse(l, r); 114 root->ch[1]->ch[0] = null; 115 root->ch[1]->push_up(); 116 root->push_up(); 117 int k = N - r + l - 1; 118 get_range(1, k); 119 splay(select(root, k), null); 120 splay(select(root, k + 1), root); 121 root->ch[1]->ch[0] = x; 122 x->pre = root->ch[1]; 123 root->ch[1]->push_up(); 124 root->push_up(); 125 } 126 inline void travle(Node *x){ 127 if (x != null){ 128 x->push_down(); 129 travle(x->ch[0]); 130 printf("%d ", x->v); 131 travle(x->ch[1]); 132 } 133 } 134 inline void travle(){ 135 get_range(1, N); 136 Node *x = root->ch[1]->ch[0]; 137 travle(x); 138 } 139 }Splay; 140 int main(){ 141 #ifdef LOCAL 142 freopen("in.txt", "r", stdin); 143 freopen("out.txt", "w+", stdout); 144 #endif 145 int a, b, n, m; 146 while (~scanf("%d %d", &n, &m)){ 147 Splay.init(n); 148 while (m--){ 149 scanf("%d %d", &a, &b); 150 Splay.cut_link(a, b); 151 } 152 Splay.travle(); 153 } 154 return 0; 155 }