Functional Array Processing

Write a function that will search an array of integers for two values that equal 2nd argument.

let arrayInput = [3, 34, 4, 12, 5, 2];

// function to find two values in inputArray that equal target
function findPairForSum(integers, target) {
  let result = [];

  var subtree = (givenArray, el2Eliminate) => {
    let copy = [];
    givenArray.forEach( (el, i, ar) => {
      if (i !== el2Eliminate) {
        copy.push(el);
      }
    });
    return copy;
  }

  integers.forEach( (el, i, ar) => {
    let eliminate = i;
    let choppedArray = subtree(ar, i);
    choppedArray.forEach( (el, i, ar) => {
      if (eliminate + el == target) {
        result.push(eliminate);
        result.push(el);
        return result;
      }
    });
  });
  return result;
}

// test 1
var pair = findPairForSum(arrayInput, 9);
console.log(`9 = ${pair}`); // --> [4, 5]

// test 2
pair = findPairForSum(arrayInput, 14);
console.log(`14 = ${pair}`); // --> [12, 2]

// test 3
pair = findPairForSum(arrayInput, 99);
console.log(`99 = ${pair}`); // --> [,]