BZOJ 1669: [Usaco2006 Oct]Hungry Cows饥饿的奶牛|动态规划

刷水又来了一发

裸的最长上升子序列

然而我并没有写二分而是写的暴力

#include<cstdio>#include<cstdlib>#include<cstring>#include<cmath>#include<queue>#include<vector>#include<set>#include<map>#include<algorithm>#include<iostream>#define T 5050using namespace std;int sc(){int i=0;char c=getchar();while(c>'9'||c<'0')c=getchar();while(c>='0'&&c<='9')i=i*10+c-'0',c=getchar();return i;}int a[T],f[T],st[T];int top,n,ans;int search(int x){int l=1;while(l<=top&&x>st[l])l++;if(l>top)st[++top]=x;else st[l]=x;return l;}int main(){n=sc();for(int i=1;i<=n;i++)a[i]=sc();for(int i=1;i<=n;i++)f[i]=search(a[i]),ans=max(f[i],ans);cout << ans;return 0;}