LCS LIS

 1 #include<cstdio> 
 2 #include<cstring>
 3 #include<cmath>
 4 #include<ctime>
 5 #include<iostream>
 6 #include<algorithm>
 7 #include<queue>
 8 #include<set>
 9 #define inf (0x7fffffff)
10 #define l(a) ((a)<<1)
11 #define r(a) ((a)<<1|1)
12 #define b(a) (1<<(a))
13 #define rep(i,a,b) for(int i=a;i<=(b);i++)
14 #define clr(a) memset(a,0,sizeof(a))
15 typedef long long ll;
16 typedef unsigned long long ull;
17 using namespace std;
18 int readint(){
19     int t=0,f=1;char c=getchar();
20     while(!isdigit(c)){
21         if(c==‘-‘) f=-1;
22         c=getchar();
23     }
24     while(isdigit(c)){
25         t=(t<<3)+(t<<1)+c-‘0‘;
26         c=getchar();
27     }
28     return t*f;
29 }
30 const int maxn=100009;
31 int n,ans,a[maxn],b[maxn],p[maxn],d[maxn],g[maxn];
32 int main(){
33     //freopen("#input.txt","r",stdin);
34     //freopen("#output.txt","w",stdout);
35     n=readint();
36     rep(i,1,n) a[i]=readint();
37     rep(i,1,n) b[i]=readint();
38     rep(i,1,n) p[a[i]]=i;
39     rep(i,1,n) b[i]=p[b[i]];
40     d[1]=1;g[1]=a[1];
41     rep(i,1,n){
42         if(b[i]>g[ans]){
43             g[++ans]=b[i];
44             d[i]=ans;
45             continue; 
46         }
47         int t=lower_bound(g+1,g+ans+1,b[i])-g;
48         g[t]=b[i];
49         d[i]=t;
50     }
51     cout<<ans<<endl;
52     //fclose(stdin);
53     //fclose(stdout);
54     return 0;
55 }