Find the sum which is closest to a target number using three numbers in an array or 3Sum closest problem in Go (Golang)

Overview

The objective is to find the sum using three triplets in the given array such that the sum is closest to a given target sum.

For

Input Array: [0,2,3,-1] Target Sum:6
Output: 5 . It can be formed using 0+2+3 

Program

Below is the program for the same

package main

import (
	"fmt"
	"math"
	"sort"
)

func main() {
	output := threeSumClosest([]int{0, 2, 3, -1}, 6)
	fmt.Println(output)
}

func threeSumClosest(nums []int, target int) int {

	numsLength := len(nums)

	closestSum := 0
	nearest := 10000

	sort.Slice(nums, func(i, j int) bool {
		return nums[i] < nums[j]
	})

	for k := 0; k < numsLength-2; k++ {
		i := k + 1
		j := numsLength - 1
		for i < j {
			sum := nums[k] + nums[i] + nums[j]
			absSum := int(math.Abs(float64(target - sum)))

			if absSum < nearest {
				nearest = absSum
				closestSum = sum
			}

			if nums[k]+nums[i]+nums[j] > target {
				j--
			} else {
				i++
			}
		}
	}

	return closestSum
}

Output

5

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