﻿ Java - Find all triplets equal to a sum in a unsorted array

# Java: Find all triplets equal to a given sum in a unsorted array of integers

## Java Array: Exercise-74 with Solution

Write a Java program to find all triplets equal to a given sum in an unsorted array of integers.

Example:
Input :
nums = { 1, 6, 3, 0, 8, 4, 1, 7 }
Output:
Triplets of sum 7
(0 1 6)
(0 3 4)

Sample Solution:

Java Code:

``````// Import the necessary Java classes.
import java.util.Arrays;
// Define the 'solution' class.
class solution {
// Define a method to find and print all triplets with a given sum.
public static void find_and_print_all_Triplets(int[] nums, int sum, int alen)
{
System.out.println("\nTriplets of sum " + sum);
// Iterate through the array, leaving space for at least three elements.
for (int i = 0; i <= alen - 3; i++)
{
int k = sum - nums[i];
int l_index = i + 1, h_index = nums.length - 1;
// Use a two-pointer approach to find triplets that sum up to 'k'.
while (l_index < h_index)
{
if (nums[l_index] + nums[h_index] < k) {
l_index++;
}
else if (nums[l_index] + nums[h_index] > k) {
h_index--;
}
else {
// Print the triplet and adjust the pointers.
System.out.println("(" + nums[i] + " " + nums[l_index] + " " + nums[h_index] + ")");
l_index++;
h_index--;
}
}
}
}
// Define the main method for running the program.
public static void main(String[] args)
{
// Initialize the array and its length.
int[] nums = { 1, 6, 3, 0, 8, 4, 1, 7 };
int alen = nums.length;
System.out.println("\nOriginal array: " + Arrays.toString(nums));
// Sort the array in ascending order.
Arrays.sort(nums);
int sum = 7;
// Call the 'find_and_print_all_Triplets' method to find and print triplets with the given sum.
find_and_print_all_Triplets(nums, sum, alen);
}
}
```
```

Sample Output:

```Original array: [1, 6, 3, 0, 8, 4, 1, 7]

Triplets of sum 7
(0 1 6)
(0 3 4)
```

Flowchart: Java Code Editor:

Previous Java Exercise: Write a Java program to sort a given array of distinct integers where all its numbers are sorted except two numbers.
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