Why won't it verify?

package com.codegym.task.task04.task0419;

/*
Maximum of four numbers

*/

import java.io.*;

public class Solution {
    public static void main(String[] args) throws Exception {
        BufferedReader key = new BufferedReader(new InputStreamReader(System.in));
        int[] a ={ Integer.parseInt(key.readLine()),
                 Integer.parseInt(key.readLine()),
                 Integer.parseInt(key.readLine()),
                Integer.parseInt(key.readLine())
                    };

            int maxVal = Integer.MIN_VALUE;

        for (int i = 0; i < a.length; i++) {
            if(a[i]>maxVal)
                maxVal=a[i];
        }
        System.out.println(maxVal);

    }
}

int[] valueArray = new int[3];

int[] valueArray = new int[4];

for (int fillArray = 0; fillArray<3; fillArray++)
// will be
for (int fillArray = 0; fillArray<4; fillArray++)
// and
 for (int i = 1; i<4; i++)