js去除重复字符

function removeDuplicateCharacters(str) {
  return [...new Set(str)].join('');
}

const input = "javascript";
const result = removeDuplicateCharacters(input);
console.log(result); // 输出: "javscri"

function removeDuplicateCharacters(str) {
  return str.replace(/(.)(?=.*\1)/g, '');
}

const input = "javascript";
const result = removeDuplicateCharacters(input);
console.log(result); // 输出: "javscri"

function removeDuplicateCharacters(str) {
  let seen = {};
  let result = '';
  for (let char of str) {
    if (!seen[char]) {
      seen[char] = true;
      result += char;
    }
  }
  return result;
}

const input = "javascript";
const result = removeDuplicateCharacters(input);
console.log(result); // 输出: "javscri"

function removeDuplicateCharacters(str) {
  return str.split('').filter((char, index, arr) => arr.indexOf(char) === index).join('');
}

const input = "javascript";
const result = removeDuplicateCharacters(input);
console.log(result); // 输出: "javscri"