Convert a string in a number

let myInput = "one billion one million nineteen" //take the input here
let splitMyInput = myInput.split(" ") //get the word of my input
let storeData = [] //a array what contain the integer value
let finalRes = 0 //to store the final number what is convert from string

//main function
splitMyInput.map((element, ind) => {
    if(element){ //if the element is true the it will executed
        let myInputString = element.toLowerCase() //convert the string to lower case
        let currentNumber = findWord(myInputString) //find the number
        let myArraySecondData = splitMyInput[ind + 1] //get the second data of the splitMyInput array which is the split array
        if(myArraySecondData){ //if the second data exist it will execute
            let secondData = myArraySecondData.toLowerCase() //convert the second data to lower case
            if(secondData == "hundred" || secondData == "thousand" || secondData == "million" || secondData == "billion" || secondData == "lac") { //check that is there have any hundred.... etc data as a second data ref to the current tacking data
                storeData.push(currentNumber)
                secondData = findWord(secondData) //get the second data in integer format
                let getTheNumber = findWord(secondData)
                let calculation = secondData * currentNumber
                finalRes += calculation //store the sum in to tha mail final result
                getTheValue(storeData,getTheNumber)
            }
        }else if(myInputString == "hundred" || myInputString == "thousand" || myInputString == "million" || myInputString == "billion" || myInputString == "lac"){
            return 0 //if the current tacking string is these then it will return 0
        }else{
            finalRes += currentNumber //store the sum in to final res variable.
            }
        }
})

//if the value is hundred, thousand, million,billion, lac then it will executed
function getTheValue (arr, str){
    let [myInputString, storeData] = [str, arr] //store the argument variable
    myInputString == "hundred" &&   (finalRes += storeData[storeData.length - 2] * storeData[storeData.length - 1])
    myInputString == "thousand" &&  (finalRes += storeData[storeData.length - 2] * storeData[storeData.length - 1])
    myInputString == "million" &&   (finalRes += storeData[storeData.length - 2] * storeData[storeData.length - 1])
    myInputString == "billion" &&   (finalRes += storeData[storeData.length - 2] * storeData[storeData.length - 1])
    myInputString == "lac" &&   (finalRes += storeData[storeData.length - 2] * storeData[storeData.length - 1])
}


//convert  the string in to a data here
function findWord (string){
    let [str, res] = [string]
    switch(str){
        case "one": {
           res = 1;
           break
        }
        case "two": {
           res = 2;
           break
        }
        case "three": {
           res = 3;
           break
        }
        case "four": {
           res = 4;
           break
        }
        case "five": {
           res = 5;
           break
        }
        case "six": {
           res = 6;
           break
        }
        case "seven": {
           res = 7;
           break
        }
        case "eight": {
           res = 8;
           break
        }
        case "nine": {
           res = 9;
           break
        }
        case "ten": {
           res = 10;
           break
        }
        case "eleven": {
           res = 11;
           break
        }
        case "twelve": {
           res = 12;
           break
        }
        case "thirteen": {
           res = 13;
           break
        }
        case "fourteen": {
           res = 14;
           break
        }
        case "fifteen": {
           res = 15;
           break
        }
        case "sixteen": {
           res = 16;
           break
        }
        case "seventeen": {
           res = 17;
           break
        }
        case "eighteen": {
           res = 18;
           break
        }
        case "nineteen": {
           res = 19;
           break
        }
        case "twenty": {
           res = 20;
           break
        }
        case "thirty": {
           res = 30;
           break
        }
        case "forty": {
           res = 40;
           break
        }
        case "fifty": {
           res = 50;
           break
        }
        case "sixty": {
           res = 60;
           break
        }
        case "seventy": {
           res = 70;
           break
        }
        case "eighty": {
           res = 80;
           break
        }
        case "ninety": {
           res = 90;
           break
        }
        case "hundred": {
           res = 100
           break
        }
        case "thousand": {
           res = 1000
           break
        }
        case "million": {
           res = 1000000
           break
        }
        case "billion": {
           res = 1000000000
           break
        }
        case "lac": {
           res = 100000
           break
        }
    }
    return res
} //find the word function


console.log(finalRes); //print the main conversion here