function A(r, c, def) {
var arr = [];
for (var i = 0; i < r; i++) arr[i] = Array(c).fill(def);
return arr;
}
function B(r, c, def) {
var arr = new Array(r);
for (var i = 0; i < arr.length; i++) arr[i] = new Array(c).fill(def);
return arr;
}
function C(r, c, def) {
var arr = Array(r);
for (var i = 0; i < arr.length; i++) arr[i] = Array(c).fill(def);
return arr;
}
function D(r, c, def) {
// strange, but works
var arr = [];
for (var i = 0; i < r; i++) {
arr.push([]);
arr[i].push(Array(c));
}
for (var i = 0; i < r; i++) for (var j = 0; j < c; j++) arr[i][j]=def
return arr;
}
function E(r, c, def) {
let array = [[]];
for (var x = 0; x < c; x++) {
array[x] = [];
for (var y = 0; y < r; y++) array[x][y] = def;
}
return array;
}
function F(r, c, def) {
var makeArray = function(dims, arr) {
if (dims[1] === undefined) {
return Array(dims[0]).fill(def);
}
arr = Array(dims[0]);
for (var i = 0; i < dims[0]; i++) {
arr[i] = Array(dims[1]);
arr[i] = makeArray(dims.slice(1), arr[i]);
}
return arr;
}
return makeArray([r, c]);
}
function G(r, c, def) {
var a = [];
while (a.push(Array(c).fill(def)) < r);
return a;
}
function H(r,c, def) {
function createArray(length) {
var arr = new Array(length || 0),
i = length;
if (arguments.length > 1) {
var args = Array.prototype.slice.call(arguments, 1);
while(i--) arr[length-1 - i] = createArray.apply(this, args).fill(def);
}
return arr;
}
return createArray(r,c);
}
function I(r, c, def) {
return [...Array(r)].map(x => Array(c).fill(def));
}
function J(r, c, def) {
return Array(r).fill(0).map(() => Array(c).fill(def));
}
function K(r, c, def) {
return Array.from(Array(r), () => Array(c).fill(def));
}
function L(r, c, def) {
return Array.from({length: r}).map(e => Array(c).fill(def));
}
function M(r, c, def) {
return Array.from({length: r}, () => Array.from({length: c}, () => def));
}
function N(r, c, def) {
let arr={};
for (var i = 0; i < r; i++) for (var j = 0; j < c; j++) arr[[i,j]]=def;
return arr;
}
// -----------------------------------------------
// SHOW
// -----------------------------------------------
log = (t, f) => {
let A = f(1000,1000,7); // create array with 1000 rows and 1000 columns,
// each array cell initilised by 7
A[800][900] = 5 // 800nd row and 901nd column set to 5
console.log(`${t}[1][2]: ${A[1][2]}, ${t}[800][901]: ${A[800][900]}`);
}
log2 = (t, f) => {
let A = f(1000,1000,7); // create array with 1000 rows and 1000 columns,
// each array cell initilised by 7
A[[800,900]] = 5 // 800nd row 900nd column set to 5
console.log(`${t}[1][2]: ${A[[1,2]]}, ${t}[800][900]: ${A[[800,900]]}`);
}
log('A', A);
log('B', B);
log('C', C);
log('D', D);
log('E', E);
log('F', F);
log('G', G);
log('H', H);
log('I', I);
log('J', J);
log('K', K);
log('L', L);
log('M', M);
log2('N', N);
This is presentation of solutions - not benchmark