题解 | #拦截导弹#

import java.util.Scanner;

// 注意类名必须为 Main, 不要有任何 package xxx 信息
public class Main {
    public static void main(String[] args) {
		
		Scanner scanner = new Scanner(System.in);
		while (scanner.hasNext()) {
			int n = scanner.nextInt();
			
			int[] arr = new int[n];
			
			int[] dp = new int[n];
			for (int i = 0; i < n; i++) {
				arr[i] = scanner.nextInt();
				dp[i] = 1;	//初始化dp[i]为1，最少拦截1枚
			}
			
			int answer = 0;
			for (int i = 0; i < dp.length; i++) {
				for (int j = 0; j < i; j++) {
					if(arr[j] >= arr[i]) {	//可以把i拼到以a[j]为结尾的递减子序列中
						dp[i] = Math.max(dp[i], dp[j] + 1);
					}
				}
				answer = Math.max(answer, dp[i]);
			}
			
			System.out.println(answer);
		}
	}
}