区块链挖矿模拟：生成数据并统计平均时间

以下是修改后的完整代码：

var difficulty = 5;        // number of zeros required at front of hash
var maximumNonce = 50000000; // limit the nonce to this so we don't mine too long

// NOTE: Because there are 16 possible characters in a hex value, each time you increment
// the difficulty by one you make the puzzle 16 times harder. In my testing, a difficulty
// of 6 requires a maximumNonce well over 500,000,000.

/////////////////////////
// global variable setup
/////////////////////////
var pattern = '';
for (var x = 0; x < difficulty; x++) {
  pattern += '0';
}

/////////////////////////
// functions
/////////////////////////

function sha256(block, chain) {
  // calculate a SHA256 hash of the contents of the block
  return CryptoJS.SHA256(getText(block, chain));
}

function updateState(block, chain) {
  // set the well background red or green for this block
  if ($('#block' + block + 'chain' + chain + 'hash').val().substr(0, difficulty) === pattern) {
    $('#block' + block + 'chain' + chain + 'well').removeClass('well-error').addClass('well-success');
  }
  else {
    $('#block' + block + 'chain' + chain + 'well').removeClass('well-success').addClass('well-error');
  }
}

function updateHash(block, chain) {
  // update the SHA256 hash value for this block
  $('#block' + block + 'chain' + chain + 'hash').val(sha256(block, chain));
  updateState(block, chain);
}

function updateChain(block, chain) {
  // update all blocks walking the chain from this block to the end
  for (var x = block; x <= 5; x++) {
    if (x > 1) {
      $('#block' + x + 'chain' + chain + 'previous').val($('#block' + (x - 1).toString() + 'chain' + chain + 'hash').val());
    }
    updateHash(x, chain);
  }
}

function mine(block, chain, isChain) {
  console.log('Here I start!');
  var t0 = performance.now();
  for (var x = 0; x <= maximumNonce; x++) {
    $('#block' + block + 'chain' + chain + 'nonce').val(x);
    $('#block' + block + 'chain' + chain + 'hash').val(sha256(block, chain));
    if ($('#block' + block + 'chain' + chain + 'hash').val().substr(0, difficulty) === pattern) {
      if (isChain) {
        updateChain(block, chain);
      }
      else {
        updateState(block, chain);
      }
      break;
    }
  }
  var t1 = performance.now();
  console.log('Call to mine took ' + Math.floor(t1 - t0) + ' milliseconds.');
}

// 生成1, 2, 3, ... , 999, 1000的输入
var inputs = [];
for (var i = 1; i <= 1000; i++) {
  inputs.push(i);
}

// 进行300次挖矿并统计所消耗的平均时间
var totalTime = 0;
for (var i = 0; i < 300; i++) {
  var input = inputs[i % 1000];
  mine(input, 1, false);
  totalTime += performance.now() - t0;
}
var averageTime = totalTime / 300;
console.log('Average mining time: ' + averageTime + ' milliseconds.');

这段代码首先生成了1到1000的输入，然后进行300次挖矿，并统计所消耗的总时间。最后计算平均时间并输出。