/**
 * Returns true if the value is in the array.
 *
 * @param {Array} arr
 * @param {*} val
 * @returns {boolean}
 */

function checkValIn(arr, val) { 
  return arr.indexOf(val) > -1; 
}

var arr_cvi = [1, 2, 3, 4];
Logger.log(checkValIn(arr_cvi, 5)); // false

/**
 * Returns an array with no duplicate values.
 *
 * @param {Array} arr 
 * @returns {Array}
 */

function rmDuplicatesFrom(arr) {
  var check  = {};
  var result = [];
  var j = 0;
  for(var i = 0; i < arr.length; i++) {
    var item = arr[i];
    if(check[item] !== 1) {
      check[item] = 1;
      result[j++] = item;
    }
  }
  return result;
}

var arr_rdf = [1, 2, 3, 1, 2, 3, 4,];
Logger.log(rmDuplicatesFrom(arr_rdf)); // [1, 2, 3, 4]

/**
 * Returns an array with no empty elements.
 *
 * @param {*} x
 * @returns {Array}
 */

function rmEmptyEl(x) {
  return (x !== (undefined || ''));
}

var arr_rev = ["a",,"b",,,"c"];
Logger.log(arr_rev.filter(rmEmptyEl)); // ["a", "b", "c"]

/**
 * Returns an array of objects. Objects have two properties, count and value.
 *
 * @param {Array} arr
 * @property {value} a value found in the array
 * @property {count} count of the value in the array
 * @returns {Object[]}
 */

function countOfValIn(arr) {
  var result = [];
  var copy = arr.slice(0);
  for (var i = 0; i < arr.length; i++) {
    var myCount = 0;  
    for (var w = 0; w < copy.length; w++) {
      if (arr[i] == copy[w]) {
        myCount++;
        delete copy[w];
      }
    }
    if (myCount > 0) {
      var obj   = {};
      obj.value = arr[i];
      obj.count = myCount;
      result.push(obj);
    }
  }
  return result;
}

var arr_covi  = ["a", "b", "c", "a", "b", "c", "a"];
Logger.log(countOfValIn(arr_covi)); // [{count=3.0, value=a}, {count=2.0, value=b}, {count=2.0, value=c}]

/**
 * Returns an array of the elements in both arrays.
 *
 * @param {Array} arrA
 * @param {Array} arrB
 * @returns {Array}
 */

function intersectOf(arrA, arrB) {
  var a = 0;
  var b = 0;
  var result = [];
  while( a < arrA.length && b < arrB.length ) {
    if (arrA[a] < arrB[b] ) { a++; }
    else if (arrA[a] > arrB[b] ) { b++; }
    else {
      result.push(arrA[a]);
      a++;
      b++;
    }
  }
  return result;
}

var arrA_io = [1, 2, 3];
var arrB_io = [3, 4, 5];
Logger.log(intersectOf(arrA_io, arrB_io)); // [3]

/**
 * Returns true if both arrays have the same elements in the same order.
 *
 * @param {Array} arrA
 * @param {Array} arrB
 * @returns {boolean}
 */

function compareArr(arrA, arrB) {
  if(arrA.length !== arrB.length) return false;
  for(var i = arrA.length; i--;) {
    if(arrA[i] !== arrB[i]) return false;
  }
  return true;
}

var arrA_ca = [1, 2, 3, 4, 5];
var arrB_ca = [1, 2, 3, 4, 5];
var arrC_ca = ["a", "b", "c", "d", "e"];
Logger.log(compareArr(arrA_ca, arrB_ca)); // true
Logger.log(compareArr(arrA_ca, arrC_ca)); // false

/**
 * Returns a string of array values. 
 * Elements are separated by a delimiter and a space.
 *
 * @param {Array} arr
 * @param {string} delim
 * @returns {string}
 */

function delimStrFromArr(arr, delim) {
  var _arr = rmDuplicatesFrom(arr).sort();
  var result  = "";
  for (var i = 0; i < _arr.length; i++) {
    result += _arr[i] + delim + " ";
  }
  result = result.slice(0, -2);
  return result;
}

var arr_da = ["[email protected]", "[email protected]", "[email protected]"];
Logger.log(delimStrFromArr(arr_da, ",")); // "[email protected], [email protected], [email protected]"

/**
 * Returns a string of array values.
 * Elements are separated by a delimiter and a space, each followed by a modification.
 *
 * @param {Array} arr
 * @param {string} delim
 * @param {string} mod Modification to append to each item in the array.
 * @returns {string}
 */

function delimStrFromArrMod(arr, delim, mod) {
  var _arr = rmDuplicatesFrom(arr).sort();
  var result  = "";
  for (var i = 0; i < _arr.length; i++) {
    result += _arr[i] + mod + delim + " "; 
  }
  result = result.slice(0, -2);
  return result;
}

var arr_clfd = ["x", "z", "y"];
Logger.log(delimStrFromArrMod(arr_clfd, ",", "@example.com")); // "[email protected], [email protected], [email protected]"

/**
 * Returns an array containing all values in a two-dimensional array.
 *
 * @param {Array[]} twoDArr
 * @returns {Array} 
 */

function flattenTwoDArr(twoDArr) {
  var result = twoDArr.reduce(function(a, b) {
    return a.concat(b);
  });
  return result;
}

var sheet_fma = SpreadsheetApp.getActiveSpreadsheet().getSheetByName("Sheet1");
var val_fma   = sheet_fma.getRange("G2:H5").getValues();
Logger.log(flattenTwoDArr(val_fma).sort()); // [1, 2, 3, 4, 5, 6, 7, 8]

var ex_arrObj = [
{a: 1000, b: 1, c: 5}, 
{a: 10000, b: 2, c: 5000}, 
{a: 10, b: 2, c: 500},
{a: 1, b: 1, c: 50}
]