poj 2667 hotel 线段树
基本和poj 1823 hotel基本一样 只需加一个find函数
1 #include<iostream>
2 #include<cmath>
3 using namespace std;
4 #define MAXN 50001
5 struct node
6 {
7 int lmax,rmax,max;
8 int left,right;
9 int flag;
10 int r;
11 };
12 node tree[MAXN*4];
13 void build(int i)
14 {
15 tree[i].lmax=tree[i].rmax=tree[i].max=tree[i].right-tree[i].left+1;
16 tree[i].flag=0;
17 tree[i].r=tree[i].left;
18 if(tree[i].left==tree[i].right) return ;
19 int mid=(tree[i].left+tree[i].right)/2;
20 tree[2*i].left=tree[i].left; tree[2*i].right=mid;
21 tree[2*i+1].left=mid+1; tree[2*i+1].right=tree[i].right;
22 build(2*i); build(2*i+1);
23 }
24
25 void insert(int i,int x,int y,int c)
26 {
27 if(tree[i].left==x&&tree[i].right==y)
28 {
29 tree[i].flag=c;
30 if(c==1) tree[i].r=tree[i].lmax=tree[i].rmax=tree[i].max=0;
31 else
32 {
33 tree[i].lmax=tree[i].rmax=tree[i].max=tree[i].right-tree[i].left+1;
34 tree[i].r=tree[i].left;
35 }
36 return ;
37 }
38 if(tree[i].flag==0)
39 {
40 tree[2*i].r=tree[2*i].left;
41 tree[2*i+1].r=tree[2*i+1].left;
42 tree[2*i].flag=tree[2*i+1].flag=0;
43 tree[2*i].lmax=tree[2*i].rmax=tree[2*i].max=tree[2*i].right-tree[2*i].left+1;
44 tree[2*i+1].lmax=tree[2*i+1].rmax=tree[2*i+1].max=tree[2*i+1].right-tree[2*i+1].left+1;
45 }
46 if(tree[i].flag==1)
47 {
48 tree[2*i].r=0;
49 tree[2*i+1].r=0;
50 tree[2*i].flag=tree[2*i+1].flag=1;
51 tree[2*i].lmax=tree[2*i].rmax=tree[2*i].max=0;
52 tree[2*i+1].lmax=tree[2*i+1].rmax=tree[2*i+1].max=0;
53 }
54 int mid=(tree[i].left+tree[i].right)/2;
55 if(y<=mid) insert(2*i,x,y,c);
56 else if(x>mid) insert(2*i+1,x,y,c);
57 else
58 {
59 insert(2*i,x,mid,c);
60 insert(2*i+1,mid+1,y,c);
61 }
62 if(tree[2*i].flag==0&&tree[2*i+1].flag==0)
63 {
64 tree[i].r=tree[i].left;
65 tree[i].flag=0;
66 tree[i].lmax=tree[i].rmax=tree[i].max=tree[i].right-tree[i].left+1;
67 }
68 else if(tree[2*i].flag==0&&tree[2*i+1].flag==1)
69 {
70 tree[i].r=tree[i].left;
71 tree[i].flag=2;
72 tree[i].lmax=tree[i].max=tree[2*i].max;
73 tree[i].rmax=0;
74 }
75 else if(tree[2*i].flag==1&&tree[2*i+1].flag==0)
76 {
77 tree[i].r=mid+1;
78 tree[i].flag=2;
79 tree[i].rmax=tree[i].max=tree[2*i+1].max;
80 tree[i].lmax=0;
81 }
82 else if(tree[2*i].flag==1&&tree[2*i+1].flag==1)
83 {
84 tree[i].r=0;
85 tree[i].flag=1;
86 tree[i].lmax=tree[i].rmax=tree[i].max=0;
87 }
88 else
89 {
90 tree[i].flag=2;
91 tree[i].max=max(tree[2*i].max,tree[2*i+1].max);
92 tree[i].max=max(tree[i].max,tree[2*i].rmax+tree[2*i+1].lmax);
93 if(tree[2*i].flag==0) tree[i].lmax=tree[2*i].max+tree[2*i+1].lmax;
94 else tree[i].lmax=tree[2*i].lmax;
95 if(tree[2*i+1].flag==0) tree[i].rmax=tree[2*i].rmax+tree[2*i+1].max;
96 else tree[i].rmax=tree[2*i+1].rmax;
97 if(tree[i].max==tree[2*i].max) tree[i].r=tree[2*i].r;
98 else if(tree[i].max==tree[2*i].rmax+tree[2*i+1].lmax) tree[i].r=mid-tree[2*i].rmax+1;
99 else if(tree[i].max==tree[2*i+1].max) tree[i].r=tree[2*i+1].r;
100 }
101 }
102 int find(int i,int x)
103 {
104 if(tree[i].left==tree[i].right)
105 return tree[i].r;
106 if(tree[2*i].max>=x)
107 return find(2*i,x);
108 if(tree[2*i].rmax+tree[2*i+1].lmax>=x)
109 return tree[2*i].right+1-tree[2*i].rmax;
110 if(tree[2*i+1].max>=x)
111 return find(2*i+1,x);
112 return tree[i].r;
113 }
114 int main()
115 {
116 int n,m;
117 scanf("%d%d",&n,&m);
118 tree[1].left=1; tree[1].right=n;
119 build(1);
120 int i;
121 int x,y,c,r;
122 for(i=1;i<=m;i++)
123 {
124 scanf("%d",&c);
125 if(c==1)
126 {
127 scanf("%d",&x);
128 if(tree[1].max<x) printf("0\n");
129 else
130 {
131 r=find(1,x);
132 printf("%d\n",r);
133 insert(1,r,r+x-1,1);
134 }
135 }
136 if(c==2)
137 {
138 scanf("%d%d",&x,&y);
139 insert(1,x,x+y-1,0);
140 }
141 }
142 return 0;
143 }
