A-Gentle-Introduction-to-Computer-Algorithms/nim.html at master · tatsuhirotsuchiya/A-Gentle-Introduction-to-Computer-Algorithms · GitHub

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<!DOCTYPE html>
<html>
<head>
<meta charset=utf-8>
<script type="text/javascript">
var p0 = parseInt(prompt('Pile 0?'), 10);
var p1 = parseInt(prompt('Pile 1?'), 10);
var p2 = parseInt(prompt('Pile 2?'), 10);

function findAllStrategies(p0, p1, p2) {
  var strategies = [];
  for (var i = p0; i >= 1; i -= 1)
    strategies.push([i, 0, 0]);
  for (i = 1; i <= p1; i += 1)
    strategies.push([0, i, 0]);
  for (i = 1; i <= p2; i += 1)
    strategies.push([0, 0, i]);
  return strategies;
}

function findWinner(p0, p1, p2, player, nextplayer) {
  if (p0 === 0 && p1 === 0 && p2 === 0)
    return player;
  var allStrategies = findAllStrategies(p0, p1, p2);
  var s;
  for (var i = 0; i < allStrategies.length; i += 1) {
    s = allStrategies[i];
    if (findWinner(p0 - s[0], p1 - s[1], p2 - s[2], nextplayer,
        player) === player)
      return player;
  }
  return nextplayer;
}

var amIWinner = false;
var allStrategies = findAllStrategies(p0, p1, p2);
var s;
for (var i = 0; i < allStrategies.length; i += 1) {
  s = allStrategies[i];
  if (findWinner(p0 - s[0], p1 - s[1], p2 - s[2], 'YOU', 'I')
      === 'I') {
    amIWinner = true;
    break;
 }
}

if (amIWinner === false) {
  if (p0 >= p1 && p0 >= p2)
    s = [1, 0, 0];
  else if (p1 >= p2)
    s = [0, 1, 0];
  else
    s = [0, 0, 1];
}

document.write(amIWinner + '<br>');
document.write('State: ' + [p0, p1, p2] + '<br>');
document.write('Strategies: ' + s);
</script>
</head>
<body>
</body>
</html>