1 #include<cstdio>
2 #include<cstdlib>
3 const int mod =1000000007;
4 const int inf = ~0u>>2;
5 const int maxn = 200010;
6 int lim;
7 struct SplayTree {
8 19. int sz[maxn];
9 20. int ch[maxn][2];
10 21. int pre[maxn];
11 22. int rt,top;
12 23. inline void up(int x){
13 24. sz[x] = cnt[x] + sz[ ch[x][0] ] + sz[ ch[x][1] ];
14 25. }
15 26. inline void Rotate(int x,int f){
16 27. int y=pre[x];
17 28. ch[y][!f] = ch[x][f];
18 29. pre[ ch[x][f] ] = y;
19 30. pre[x] = pre[y];
20 31. if(pre[x]) ch[ pre[y] ][ ch[pre[y]][1] == y ] =x;
21 32. ch[x][f] = y;
22 33. pre[y] = x;
23 34. up(y);
24 35. }
25 36. inline void Splay(int x,int goal){//将x旋转到goal的下面
26 37. while(pre[x] != goal){
27 38. if(pre[pre[x]] == goal) Rotate(x , ch[pre[x]][0] == x);
28 39. else {
29 40. int y=pre[x],z=pre[y];
30 41. int f = (ch[z][0]==y);
31 42. if(ch[y][f] == x) Rotate(x,!f),Rotate(x,f);
32 43. else Rotate(y,f),Rotate(x,f);
33 44. }
34 45. }
35 46. up(x);
36 47. if(goal==0) rt=x;
37 48. }
38 49. inline void RTO(int k,int goal){//将第k位数旋转到goal的下面
39 50. int x=rt;
40 51. while(sz[ ch[x][0] ] != k-1) {
41 52. if(k < sz[ ch[x][0] ]+1) x=ch[x][0];
42 53. else {
43 54. k-=(sz[ ch[x][0] ]+1);
44 55. x = ch[x][1];
45 56. }
46 57. }
47 58. Splay(x,goal);
48 59. }
49 60. inline void vist(int x){
50 61. if(x){
51 62. printf("结点%2d : 左儿子 %2d 右儿子 %2d %2d sz=%d\n",x,ch[x][0],ch[x][1],val[x],sz[x]);
52 63. vist(ch[x][0]);
53 64. vist(ch[x][1]);
54 65. }
55 66. }
56 67. inline void Newnode(int &x,int c){
57 68. x=++top;
58 69. ch[x][0] = ch[x][1] = pre[x] = 0;
59 70. sz[x]=1; cnt[x]=1;
60 71. val[x] = c;
61 72. }
62 73. inline void init(){
63 74. ans=0;type=-1;
64 75. ch[0][0]=ch[0][1]=pre[0]=sz[0]=0;
65 76. rt=top=0; cnt[0]=0;
66 77. Newnode(rt,-inf);
67 78. Newnode(ch[rt][1],inf);
68 79. pre[top]=rt;
69 80. sz[rt]=2;
70 81. }
71 82. inline void Insert(int &x,int key,int f){
72 83. if(!x) {
73 84. Newnode(x,key);
74 85. pre[x]=f;
75 86. Splay(x,0);
76 87. return ;
77 88. }
78 89. if(key==val[x]){
79 90. cnt[x]++;
80 91. sz[x]++;
81 92. return ;
82 93. }else if(key<val[x]) {
83 94. Insert(ch[x][0],key,x);
84 95. } else {
85 96. Insert(ch[x][1],key,x);
86 97. }
87 98. up(x);
88 99. }
89 100. void Del(){
90 101. int t=rt;
91 102. if(ch[rt][1]) {
92 103. rt=ch[rt][1];
93 104. RTO(1,0);
94 105. ch[rt][0]=ch[t][0];
95 106. if(ch[rt][0]) pre[ch[rt][0]]=rt;
96 107. }
97 108. else rt=ch[rt][0];
98 109. pre[rt]=0;
99 110. up(rt);
100 111. }
101 112. void findpre(int x,int key,int &ans){
102 113. if(!x) return ;
103 114. if(val[x] <= key){
104 115. ans=x;
105 116. findpre(ch[x][1],key,ans);
106 117. } else
107 118. findpre(ch[x][0],key,ans);
108 119. }
109 120. void findsucc(int x,int key,int &ans){
110 121. if(!x) return ;
111 122. if(val[x]>=key) {
112 123. ans=x;
113 124. findsucc(ch[x][0],key,ans);
114 125. } else
115 126. findsucc(ch[x][1],key,ans);
116 127. }
117 128. void solve() {
118 129. int a,b,x,y;
119 130. scanf("%d%d",&a,&b);
120 131. if(a==type || sz[rt]==2){
121 132.
122 133. Insert(rt,b,0),type=a;
123 134. //printf("type=%d\n",type);
124 135. }
125 136. else {
126 137. findpre(rt,b,x);
127 138. findsucc(rt,b,y);
128 139. if(abs(val[x]-b) <= abs(val[y]-b)) {
129 140. ans+=abs(val[x]-b);
130 141. ans%=mod;
131 142. Splay(x,0);
132 143. Del();
133 144. }
134 145. else {
135 146. ans+=abs(val[y]-b);
136 147. ans%=mod;
137 148. Splay(y,0);
138 149. Del();
139 150. }
140 151. }
141 152. //spt.vist(rt);
142 153. }
143 154. int cnt[maxn];
144 155. int val[maxn];
145 156. int type;
146 157. int ans;
147 158.}spt;
148 159.int main()
149 160.{
150 161. int n;
151 162. scanf("%d",&n);
152 163. spt.init();
153 164. while(n--) spt.solve();
154 165. printf("%d\n",spt.ans);
155 166. return 0;
156 }
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