1DPeakFinder.js

const inputArr = JSON.parse(process.argv[2]);
console.log(process.argv);
console.log(inputArr);

let midPoint = 0;
if(inputArr.length > 0) {
  if(inputArr.length % 2 == 0) {
    midPoint = (inputArr.length / 2) - 1;
  }
  else {
    midPoint = (inputArr.length - 1) / 2;
    console.log( inputArr.length, (inputArr.length - 1)/2, midPoint);
  }
}

let PeaksArray = [];

addToPeaks(midPoint);
console.log("The peaks are : ", PeaksArray);

function addToPeaks(midPoint) {
  if(midPoint == 0) {
    if(inputArr[0] >= inputArr[1]) {
      PeaksArray.push(inputArr[0]);
    }
  }
  else if(midPoint == inputArr.length - 1) {
    if(inputArr[inputArr.length - 1] >= inputArr[inputArr.length - 2]);
    PeaksArray.push(inputArr[inputArr.length - 1]);
  }
  else if(inputArr[midPoint] >= inputArr[midPoint + 1] && inputArr[midPoint] >= inputArr[midPoint - 1]) {
    PeaksArray.push(inputArr[midPoint]);
    addToPeaks(midPoint = midPoint + Math.floor(midPoint / 2));
    //addToPeaks(Math.floor(midPoint / 2));
  }
  else if ( inputArr[midPoint] < inputArr[midPoint + 1] ) {
    midPoint = midPoint + Math.floor(midPoint / 2);
    addToPeaks(midPoint);
  }
  else if( inputArr[midPoint] < inputArr[midPoint - 1]) {
    midPoint = Math.floor(midPoint / 2);
    addToPeaks(midPoint);
  }
}