java get the closest pair to a given sum in two arrays

To get the closest pair of elements from two arrays whose sum is closest to a given value in Java, you can use a brute force approach where you iterate over both arrays and keep track of the closest pair found so far.

Here is an example of how to get the closest pair of elements from two arrays:

int[] array1 = {1, 2, 3};
int[] array2 = {4, 5, 6};
int target = 5;
int closestDifference = Integer.MAX_VALUE;
int closestSum = 0;

for (int i = 0; i < array1.length; i++) {
    for (int j = 0; j < array2.length; j++) {
        int sum = array1[i] + array2[j];
        int difference = Math.abs(target - sum);
        if (difference < closestDifference) {
            closestDifference = difference;
            closestSum = sum;
        }
    }
}

// closestSum will be 6

In the code above, we use two nested loops to iterate over both arrays. For each pair of elements, we calculate the sum and the absolute difference between the sum and the target value. If the difference is smaller than the closest difference found so far, we update the closest difference and the closest sum.

At the end of the loops, the closestSum variable will contain the sum of the closest pair of elements found.

Note that this approach has a time complexity of O(n^2), where n is the length of the arrays. This means that it may not be suitable for large arrays. If you need a more efficient solution, you can use a different approach, such as sorting the arrays and using a binary search to find the closest pair.