replaces array items in pairs

replacing-in-pairs.js

console.clear()

let used = [],
    replaced = []
/* 
TODO: only needed for early testing. can del
len = 20,
createArr = function(N) {
  return Array.apply(null, {
    length: N
  }).map(Number.call, Number)
} */
;

/* let arr = createArr(len); */
//TODO: need regex based splitting function
let arr = ["In", "specific", "applications", "(such", "as", "digital", "distribution", "broadcast,", "similar", "toGoogle", "Play", "Store),", "smartphones", "can", "be", "used", "to", "carry", "out", "some", "attacks", "andtherefore", "increase", "the", "threats", "of", "such", "attacks"]

let pair = function(srcArr, usedArr) {
    let count = 0,
        genNum = null,
        pair = [];
    do {
        let genNum = Math.floor(Math.random() * srcArr.length);
        if (usedArr.indexOf(genNum) == -1) {
            pair.push(genNum);
            usedArr.push(genNum);
            count++;
        }
    } while (count < 2)
    return pair;
}


let makeUsedArr = function(srcArr, usedArr) {
    do {
        pair(srcArr, usedArr);
    } while (srcArr.length > usedArr.length)
    return usedArr;
}


let replace = function(srcArr, usedArr, replacedArr) {
    //FIXME: feels weird, like double duty
    let fullUsedArr = makeUsedArr(srcArr, usedArr);
    fullUsedArr.forEach(function(each) {
        replacedArr.push(srcArr[each]);
    })
    return replacedArr;
}



console.log('replace', replace(arr, used, replaced))