Не знаю правильно или нет, что за двоеточие такое?
package com.javarush.task.pro.task05.task0504;
import java.util.Arrays;
/*
Объединяем массивы
*/
public class Solution {
public static int[] firstArray = new int[]{0, 1, 2, 3, 4, 5, 6, 7, 8, 9};
public static int[] secondArray = new int[]{10, 11, 12, 13, 14, 15, 16, 17, 18, 19};
public static int[] resultArray;
public static void main(String[] args) {
int length = firstArray.length + secondArray.length; //add the length of firstArray into secondArray
int[] resultArray = new int[length]; //resultant array
int pos = 0;
for (int element : firstArray) {
resultArray[pos] = element;
pos++; //increases position by 1
}
for (int element : secondArray) {
resultArray[pos] = element;
pos++;
}
for (int i = 0; i < resultArray.length; i++) {
System.out.print(resultArray[i] + ", ");
}
}
}