public class MaxDistanceFinder {
/**
* Finds the maximum distance between two values in an array.
*
* Distance = abs(indexA - indexB)
*
* @param arr Input array
* @param value1 First value to search for
* @param value2 Second value to search for
* @return Maximum distance, or -1 if either value is not found
*/
public static int maxDistanceBetweenValues(int[] arr,
int value1,
int value2) {
int first1 = -1;
int last1 = -1;
int first2 = -1;
int last2 = -1;
// Find the first and last occurrence of both values
for (int i = 0; i < arr.length; i++) {
if (arr[i] == value1) {
if (first1 == -1) {
first1 = i;
}
last1 = i;
}
if (arr[i] == value2) {
if (first2 == -1) {
first2 = i;
}
last2 = i;
}
}
// One or both values do not exist
if (first1 == -1 || first2 == -1) {
return -1;
}
// Check the two extreme combinations
int distance1 = Math.abs(first1 - last2);
int distance2 = Math.abs(first2 - last1);
return Math.max(distance1, distance2);
}
public static void main(String[] args) {
int[] arr = {
2, 3, 7, 3, 3, 4, 8, 8, 8, 11, 9, 1, 3
};
int result = maxDistanceBetweenValues(arr, 3, 8);
System.out.println("Maximum distance between 3 and 8: " + result);
}
}
/*
run:
Maximum distance between 3 and 8: 7
*/
