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JavaScript

function shuffle(deck, i) {
    if (i <= 0)
        return;
    else {
        swap(deck[rand(0,i-1)], deck[i-1]);
        shuffle(deck, i - 1);
    }
}

Call with shuffle(deck,52)

A complete working example (had to modify swap slightly because there is no pass-by-reference of ints in JavaScript):

function rand(min, max) { return Math.floor(Math.random()*(max-min+1)+min); }
function swap(deck, i, j) {
    var t=deck[i];
    deck[i] = deck[j];
    deck[j] = t;
}

function shuffle(deck, i) {
    if (i <= 0)
        return;
    else {
        swap(deck, rand(0,i-1), i-1);
        shuffle(deck, i - 1);
    }
}

// create deck
var deck=[];
for(i=0;i<52;i++)deck[i]=i;
document.writeln(deck);
shuffle(deck,52);
document.writeln(deck);

JavaScript

NOTE: This solution is technically not correct because it uses a second parameter, i, in the call to shuffle, which counts as an external variable.

function shuffle(deck, i) {
    if (i <= 0)
        return;
    else {
        swap(deck[rand(0,i-1)], deck[i-1]);
        shuffle(deck, i - 1);
    }
}

Call with shuffle(deck,52)

A complete working example (had to modify swap slightly because there is no pass-by-reference of ints in JavaScript):

function rand(min, max) { return Math.floor(Math.random()*(max-min+1)+min); }
function swap(deck, i, j) {
    var t=deck[i];
    deck[i] = deck[j];
    deck[j] = t;
}

function shuffle(deck, i) {
    if (i <= 0)
        return;
    else {
        swap(deck, rand(0,i-1), i-1);
        shuffle(deck, i - 1);
    }
}

// create deck
var deck=[];
for(i=0;i<52;i++)deck[i]=i;
document.writeln(deck);
shuffle(deck,52);
document.writeln(deck);

JavaScript

function shuffle(deck, i) {
    if (i <= 1)
        return;
    else {
        swap(deck[rand(0,i-2)], deck[i-1]);
        shuffle(deck, i - 1);
    }
}

Call with shuffle(deck,52)

A complete working example (had to modify swap slightly because there is no pass-by-reference of ints in JavaScript):

function rand(min, max) { return Math.floor(Math.random()*(max-min+1)+min); }
function swap(deck, i, j) {
    var t=deck[i];
    deck[i] = deck[j];
    deck[j] = t;
}

function shuffle(deck, i) {
    if (i <= 1)
        return;
    else {
        swap(deck, rand(0,i-2), i-1);
        shuffle(deck, i - 1);
    }
}

// create deck
var deck=[];
for(i=0;i<52;i++)deck[i]=i;
document.writeln(deck);
shuffle(deck,52);
document.writeln(deck);

JavaScript

function shuffle(deck, i) {
    if (i <= 0)
        return;
    else {
        swap(deck[rand(0,i-1)], deck[i-1]);
        shuffle(deck, i - 1);
    }
}

Call with shuffle(deck,52)

A complete working example (had to modify swap slightly because there is no pass-by-reference of ints in JavaScript):

function rand(min, max) { return Math.floor(Math.random()*(max-min+1)+min); }
function swap(deck, i, j) {
    var t=deck[i];
    deck[i] = deck[j];
    deck[j] = t;
}

function shuffle(deck, i) {
    if (i <= 0)
        return;
    else {
        swap(deck, rand(0,i-1), i-1);
        shuffle(deck, i - 1);
    }
}

// create deck
var deck=[];
for(i=0;i<52;i++)deck[i]=i;
document.writeln(deck);
shuffle(deck,52);
document.writeln(deck);

JavaScript

function shuffle(deck, i) {
    if (i <= 1)
        return;
    else {
        swap(deck[rand(0,i-2)], deck[i-1]);
        shuffle(deck, i - 1);
    }
}

Call with shuffle(deck,52)

JavaScript

function shuffle(deck, i) {
    if (i <= 1)
        return;
    else {
        swap(deck[rand(0,i-2)], deck[i-1]);
        shuffle(deck, i - 1);
    }
}

Call with shuffle(deck,52)

A complete working example (had to modify swap slightly because there is no pass-by-reference of ints in JavaScript):

function rand(min, max) { return Math.floor(Math.random()*(max-min+1)+min); }
function swap(deck, i, j) {
    var t=deck[i];
    deck[i] = deck[j];
    deck[j] = t;
}

function shuffle(deck, i) {
    if (i <= 1)
        return;
    else {
        swap(deck, rand(0,i-2), i-1);
        shuffle(deck, i - 1);
    }
}

// create deck
var deck=[];
for(i=0;i<52;i++)deck[i]=i;
document.writeln(deck);
shuffle(deck,52);
document.writeln(deck);