杭电1257（最少拦截系统）dp方法

import java.util.Scanner;

class P1257 {
	static int n;
	static int[] dp,a;
	public static void main(String[] args) {
		Scanner sc=new Scanner(System.in);
		while(sc.hasNext()){
			n=sc.nextInt();
			a=new int[n+1];
			for(int i=1;i<=n;i++){
				a[i]=sc.nextInt();
			}
			System.out.println(lis());
		}
	}
	public static int lis() {
		int i,j,ans,m;
		ans=1;
		dp=new int[n+1];
		dp[1]=1;
		for(i=2;i<=n;i++){
			m=0;
			for(j=1;j<=i;j++){
				if(dp[j]>m &&a[j]<a[i]){
					m=dp[j];
				}
			}
			dp[i]=m+1;
			if(dp[i]>ans){
				ans=dp[i];
			}
		}
		return ans;
	}

}