pair-pair
输入文件：pair-pair.in 输出文件：pair-pair.out 简单对比
时间限制：7 s 内存限制：64 MB
Time Limit : 7000 MS
Memory Limit : 65536 KB
Pair-Pair
Bobo is tired of all kinds of hard LIS (Longest Increasing Subsequence) problems, so he decides to make himself some easier one.
Bobo has n pairs (a1,b1),(a2,b2),…,(an,bn) where 1≤ai,bi≤m holds for all i. He defines f(i,j) be the length of longest increasing subsequence of sequence {ai,bi,aj,bj}.
It's clear that 1≤f(i,j)≤4. Bobo would like to know g(k) which is the number of pairs (i,j) where f(i,j)=k.
Note that a sequence labeled with {i1,i2,…,ik} is an increasing subsequence of {a1,a2,…,an} only if:
1≤i1
Input
The first line contains 2 integers n,m (1≤n≤105,1≤m≤103).
The i-th of the following n lines contains 2 integers ai,bi (1≤ai,bi≤m).
Output
For each set, 4 integers g(1),g(2),g(3),g(4).
Sample Input
2 4
1 2
3 4
2 1
1 1
1 1
Sample Output
0 3 0 1
4 0 0 0
注意各种特判就好了。
有时间再更新题解吧……
1 #include
2 #include
3 #include
4 #include
5 using namespace std;
6 const int maxn=100010;
7 const int maxm=1010;
8 int n,m;
9 long long a[10];
10 long long b1[maxm],b2[maxm];
11 long long b3[maxm],b4[maxm];
12
13 struct Node{
14 int a,b;
15 Node(int a_=0,int b_=0){
16 a=a_;b=b_;
17 }
18 }p[maxn];
19
20 bool cmp(Node x,Node y){
21 if(x.a!=y.a)
22 return x.a<y.a;
23 return x.b<y.b;
24 }
25
26 void Bit_Add(long long *b,int x,int d){
27 while(x<=m){
28 b[x]+=d;
29 x+=x&(-x);
30 }
31 }
32
33 int Bit_Query(long long *b,int x){
34 int ret=0;
35 while(x){
36 ret+=b[x];
37 x-=x&(-x);
38 }
39 return ret;
40 }
41
42 int rt[maxm],sum[maxn*20],ch[maxn*20][2],cnt;
43 void Insert(int pre,int &rt,int l,int r,int g,int d){
44 rt=++cnt;
45 ch[rt][0]=ch[pre][0];
46 ch[rt][1]=ch[pre][1];
47 sum[rt]=sum[pre]+d;
48 if(l==r)return;
49 int mid=(l+r)>>1;
50 if(mid>=g)Insert(ch[pre][0],ch[rt][0],l,mid,g,d);
51 else Insert(ch[pre][1],ch[rt][1],mid+1,r,g,d);
52 }
53
54 int Query(int pre,int rt,int l,int r,int a,int b){
55 if(a>b)return 0;
56 if(l>=a&&r<=b)return sum[rt]-sum[pre];
57 int mid=(l+r)>>1,ret=0;
58 if(mid>=a)ret=Query(ch[pre][0],ch[rt][0],l,mid,a,b);
59 if(mid1],ch[rt][1],mid+1,r,a,b);
60 return ret;
61 }
62
63 void Init(){
64 memset(a,0,sizeof(a));cnt=0;
65 memset(b1,0,sizeof(b1));
66 memset(b2,0,sizeof(b2));
67 memset(b3,0,sizeof(b3));
68 memset(b4,0,sizeof(b4));
69 }
70
71 int main(){
72 #ifndef ONLINE_JUDGE
73 freopen("pair-pair.in","r",stdin);
74 freopen("pair-pair.out","w",stdout);
75 #endif
76 while(scanf("%d%d",&n,&m)!=EOF){
77 Init();
78 for(int i=1;i<=n;i++)
79 scanf("%d%d",&p[i].a,&p[i].b);
80 sort(p+1,p+n+1,cmp);
81 for(int i=1,last=0;i<=n;i++){
82 long long tot=2*(i-1),tmp;
83
84 if(p[i].a<p[i].b){
85 tmp=Bit_Query(b1,m)-Bit_Query(b1,p[i].b)+Bit_Query(b2,p[i].a-1);
86 a[4]+=tmp;tot-=tmp;
87
88 tmp=Bit_Query(b1,p[i].b)-Bit_Query(b1,p[i].a);
89 tmp+=Bit_Query(b2,p[i].b-1)-Bit_Query(b2,p[i].a-1);
90
91 tmp+=Bit_Query(b3,m)-Bit_Query(b3,p[i].b)+Bit_Query(b4,p[i].a-1);
92 tmp+=Bit_Query(b2,m)-Bit_Query(b2,p[i].b);
93 for(int j=last+1;jrt[last];
94
95 tmp+=Query(rt[0],rt[p[i].a-1],1,m,p[i].b,m);
96
97 a[3]+=tmp;tot-=tmp;
98
99 Insert(rt[last],rt[p[i].a],1,m,p[i].b,1);
100
101 last=p[i].a;a[2]+=tot;
102
103 Bit_Add(b1,p[i].a,1);Bit_Add(b2,p[i].b,1);
104 }
105 else{
106 tmp=Bit_Query(b3,p[i].b)+Bit_Query(b4,m)-Bit_Query(b4,p[i].a-1);
107 a[1]+=tmp;tot-=tmp;
108
109 tmp=Bit_Query(b1,m)-Bit_Query(b1,p[i].b)+Bit_Query(b2,p[i].a-1);
110 a[3]+=tmp;tot-=tmp;
111
112 a[2]+=tot;
113 Bit_Add(b3,p[i].a,1);Bit_Add(b4,p[i].b,1);
114 }
115 }
116
117 for(int i=1;i<=n;i++){
118 if(p[i].a!=p[i].b)a[2]+=1;
119 else a[1]+=1;
120 }
121 printf("%lld %lld %lld %lld\n",a[1],a[2],a[3],a[4]);
122 }
123 return 0;
124 }
