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@davidauza-engineer
Created March 19, 2019 02:28
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Console program in Java to reverse an array created by the user.
import java.util.Arrays;
import java.util.Scanner;
public class ArrayReverse {
static int arraySize;
public static void main(String[] args) {
int[] array;
int[] reversedArray;
boolean validArraySize = false;
boolean validInteger = false;
String errorSize = "\nError. Not a valid array size. Please insert an integer number greater than 0.";
Scanner sc = new Scanner(System.in);
System.out.println("\nWelcome to the program to reverse an integer array.");
// The user is prompted to determine the size of the array
while (!validArraySize) {
System.out.println("\nPlease insert the size of the array");
if (sc.hasNextInt()) {
arraySize = sc.nextInt();
if (arraySize > 0) {
validArraySize = true;
} else {
// The user entered an integer number less or equal to 0.
System.out.println(errorSize);
}
} else {
// The user did not enter an integer number.
System.out.println(errorSize);
}
}
// The array is created with the specified size
array = new int[arraySize];
// The user is prompted to enter the value for each position of the array
for (int i = 0; i < array.length; i++) {
while (!validInteger) {
System.out.println("\nPlease insert the value for position " + i + ":");
if (sc.hasNextInt()) {
array[i] = sc.nextInt();
validInteger = true;
} else {
System.out.println("\nError. Please insert a valid integer number.");
}
}
validInteger = false;
}
sc.close();
System.out.println("\nThe array you entered is: " + Arrays.toString(array));
reversedArray = reverseArray(array);
System.out.println("\nThe reversed array is: " + Arrays.toString(reversedArray));
}
/**
* This method reverses the array specified
*
* @param pArray The array to reverse
* @return The reversed array
*/
public static int[] reverseArray(int[] pArray) {
int[] arrayToReturn = new int[arraySize];
int indexToReverse = arraySize - 1;
for (int i = 0; i < arrayToReturn.length; i++) {
arrayToReturn[i] = pArray[indexToReverse];
indexToReverse--;
}
return arrayToReturn;
}
}
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