toj 259 - 竹園崗

http://toj.tfcis.org/oj/pro/259/

正的做一次LIS 逆的再做一次LIS
然後兩邊交起來取max就過惹

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#include<bits/stdc++.h> using namespace std; #define ull unsigned long long #define ll long long #define ld long double #define PB(x) push_back(x) #define MP(x,y) make_pair(x,y) #define pii pair<int,int> #define vint vector<int> #define rz(x) resize(x) #define X first #define Y second // #define m (l+r)/2 // #define xm (x1+x2)/2 // #define ym (y1+y2)/2 #define DE cout<<"de"<<endl; #define PQ priority_queue inline int rit(){ int t=0,k=1; char c; do{ c=getchar(); if(c=='-')k=-1; }while(c<'0'||c>'9'); do{ t=t*10+c-'0'; c=getchar(); }while(c>='0'&&c<='9'); return t*k; }; int n; int a[10005],l[10005],r[10005]; int pos[10005],len; int mx; int main(){ while(cin>>n){ memset(a,0,sizeof(a)); memset(l,0,sizeof(l)); memset(r,0,sizeof(r)); memset(pos,-1,sizeof(pos)); len=0; for(int i=0;i<n;i++){ cin>>a[i]; if(a[i]>pos[len-1]){ pos[len++]=a[i]; } else{ *lower_bound(pos,pos+len,a[i])=a[i]; } l[i]=len; } len=0; memset(pos,-1,sizeof(pos)); for(int i=n-1;i>=0;i--){ if(a[i]>pos[len-1]){ pos[len++]=a[i]; } else{ *lower_bound(pos,pos+len,a[i])=a[i]; } r[i]=len; } mx=0; for(int i=0;i<n;i++){ mx=max(min(l[i],r[i])*2-1,mx); } // cout<<"l:";for(int i=0;i<n;i++)cout<<l[i]<<" ";cout<<endl; // cout<<"r:";for(int i=0;i<n;i++)cout<<r[i]<<" ";cout<<endl; cout<<mx<<endl; } }