Letter Number Cipher

Letter Number Cipher

Input Text:

Output Text:

body { font-family: sans-serif; display: flex; justify-content: center; align-items: center; min-height: 100vh; background-color: #f4f4f4; margin: 0; padding: 20px; box-sizing: border-box; } .container { background-color: #fff; padding: 30px; border-radius: 8px; box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1); width: 100%; max-width: 600px; text-align: center; } h1 { margin-top: 0; color: #333; } .input-section, .output-section { margin-bottom: 20px; text-align: left; } label { display: block; margin-bottom: 8px; font-weight: bold; color: #555; } textarea { width: 100%; padding: 10px; border: 1px solid #ccc; border-radius: 4px; font-size: 1rem; box-sizing: border-box; resize: vertical; } .button-section { margin-bottom: 20px; } button { padding: 10px 20px; margin: 0 10px; background-color: #007bff; color: white; border: none; border-radius: 4px; cursor: pointer; font-size: 1rem; transition: background-color 0.3s ease; } button:hover { background-color: #0056b3; } button:active { background-color: #004085; } document.addEventListener('DOMContentLoaded', () => { const inputTextarea = document.getElementById('inputText'); const outputTextarea = document.getElementById('outputText'); const encryptBtn = document.getElementById('encryptBtn'); const decryptBtn = document.getElementById('decryptBtn'); const letterToNumber = (char) => { const upperChar = char.toUpperCase(); const code = upperChar.charCodeAt(0); if (code >= 65 && code <= 90) { // A-Z return (code - 65 + 1).toString(); } return char; // Keep non-letters as they are }; const numberToLetter = (numStr) => { const num = parseInt(numStr, 10); if (num >= 1 && num <= 26) { return String.fromCharCode(65 + num - 1); } return numStr; // Keep non-numbers or out-of-range numbers as they are }; encryptBtn.addEventListener('click', () => { const input = inputTextarea.value; let output = ''; for (let i = 0; i < input.length; i++) { const char = input[i]; const result = letterToNumber(char); output += result; // Add space after numbers representing letters, and after non-letters // This makes decryption easier by splitting on spaces if (result.length > 1 || (result.length === 1 && char.toUpperCase() !== result)) { // It was a letter converted to a number string output += ' '; } else if (result.length === 1 && char.toUpperCase() === result) { // It was a non-letter character output += ' '; } } outputTextarea.value = output.trim(); // Trim trailing space }); decryptBtn.addEventListener('click', () => { const input = inputTextarea.value; // Split by spaces to handle the number representations const parts = input.split(' '); let output = ''; for (const part of parts) { if (part === '') { // Handle multiple spaces output += ' '; } else { output += numberToLetter(part); } } // Clean up potential extra spaces introduced by split/join logic // A simple replace handles cases like "1 2 3" -> "AB C" outputTextarea.value = output.replace(/\s+/g, ' ').trim(); }); });