Merkel Root

const crypto = require('crypto');

// Transactions
const transactions = ['T1', 'T2', 'T3', 'T4', 'T5'];

// Merkle Root Calculation
function calculateMerkleRoot(transactions) {
  if (transactions.length === 0) {
    return null;
  }

  if (transactions.length === 1) {
    return transactions[0];
  }

  const pairedTransactions = [];
  if (transactions.length % 2 !== 0) {
    transactions.push(transactions[transactions.length - 1]);
  }

  for (let i = 0; i < transactions.length; i += 2) {
    const pair = transactions[i] + transactions[i + 1];
    const hash = crypto.createHash('sha256').update(pair).digest('hex');
    pairedTransactions.push(hash);
  }

  return calculateMerkleRoot(pairedTransactions);
}

// Calculate Merkle Root
const merkleRoot = calculateMerkleRoot(transactions);

console.log('Merkle Root:', merkleRoot);