HDOJ 2071 Max Num

Problem Description
There are some students in a class, Can you help teacher find the highest student .

Input
There are some cases. The first line contains an integer t, indicate the cases; Each case have an integer n ( 1 ≤ n ≤ 100 ) , followed n students’ height.

Output
For each case output the highest height, the height to two decimal plases;

Sample Input
2
3 170.00 165.00 180.00
4 165.00 182.00 172.00 160.00

Sample Output
180.00
182.00

同一个代码！这个运行时间正好是在超时的边界！~

import java.util.Scanner;
public class Main {

    static Scanner sc=new Scanner(System.in);
    public static void main(String[] args) {
        int n=sc.nextInt();
        while(n-->0){
                int m=sc.nextInt();
                double[] a=new double[m];
                double max=a[0]=sc.nextDouble();
                for(int i=1;i<a.length;i++){
                    a[i]=sc.nextDouble();
                    if(max<a[i]){
                        max=a[i];
                    }    
                }
                System.out.printf("%.2f",max);
                System.out.println();
            }

    }
}