BZOJ3688: 折线统计

 1 #include<cstdio>
 2 #include<cstdlib>
 3 #include<cmath>
 4 #include<cstring>
 5 #include<algorithm>
 6 #include<iostream>
 7 #include<vector>
 8 #include<map>
 9 #include<set>
10 #include<queue>
11 #include<string>
12 #define inf 1000000000
13 #define maxn 100000+5
14 #define maxm 500+100
15 #define eps 1e-10
16 #define ll long long
17 #define pa pair<int,int>
18 #define for0(i,n) for(int i=0;i<=(n);i++)
19 #define for1(i,n) for(int i=1;i<=(n);i++)
20 #define for2(i,x,y) for(int i=(x);i<=(y);i++)
21 #define for3(i,x,y) for(int i=(x);i>=(y);i--)
22 #define for4(i,x) for(int i=head[x],y;i;i=e[i].next)
23 #define mod 100007
24 using namespace std;
25 inline int read()
26 {
27     int x=0,f=1;char ch=getchar();
28     while(ch<‘0‘||ch>‘9‘){if(ch==‘-‘)f=-1;ch=getchar();}
29     while(ch>=‘0‘&&ch<=‘9‘){x=10*x+ch-‘0‘;ch=getchar();}
30     return x*f;
31 }
32 int n,m,b[maxn];
33 struct rec{int x,y;}a[maxn];
34 inline bool cmp(rec a,rec b){return a.x<b.x;}
35 inline bool cmp1(int i,int j){return a[i].y<a[j].y;}
36 struct bit
37 {
38     int s[maxn];
39     inline void add(int x,int y)
40     {
41         y=(y%mod+mod)%mod;
42         for(;x<=n;x+=x&(-x))(s[x]+=y)%=mod;
43     }
44     inline int sum(int x)
45     {
46         int t=0;
47         for(;x;x-=x&(-x))(t+=s[x])%=mod;
48         return t;
49     }
50 }t[11][2];
51 int main()
52 {
53     freopen("input.txt","r",stdin);
54     freopen("output.txt","w",stdout);
55     n=read();m=read();
56     for1(i,n)a[i].x=read(),a[i].y=read();
57     sort(a+1,a+n+1,cmp);
58     for1(i,n)b[i]=i;
59     sort(b+1,b+n+1,cmp1);
60     for1(i,n)a[b[i]].y=i;
61     for1(i,n)
62     {
63      t[0][0].add(a[i].y,1);t[0][1].add(a[i].y,1);
64      for1(j,m)
65       {
66            t[j][0].add(a[i].y,t[j][0].sum(n)-t[j][0].sum(a[i].y)+t[j-1][1].sum(n)-t[j-1][1].sum(a[i].y));
67            t[j][1].add(a[i].y,t[j][1].sum(a[i].y-1)+t[j-1][0].sum(a[i].y-1));
68       }
69     }
70     printf("%d\n",(t[m][0].sum(n)+t[m][1].sum(n))%mod);    
71     return 0;
72 }