饿了么前端秋招笔试

一个数各个数位的 GCD 刚好也能被这个数本身整除，这种数字被定义为“好数字”，求给定的数组里有多少个“好数字”？没什么难度

🔍 展开代码

1.js

const rl = require("readline").createInterface({ input: process.stdin });
const inputs = [];
rl.on("line", (line) => inputs.push(line));
rl.on("close", () => {
  const queryTimes = +inputs[0];
  for (let i = 1; i < inputs.length; i += 2) {
    const n = +inputs[i];
    const nums = inputs[i + 1].split(" ").map(Number);
    const result = findGood(n, nums);
    console.log(result);
  }
});

function findGood(n, nums) {
  let answer = 0;
  for (let i = 0; i < n; i++) {
    const curNum = nums[i];
    if (curNum < 10) {
      answer++;
      continue;
    }
    // 不是个位数的情况
    const numArr = Array.from("" + curNum).map(Number);
    const gcd = generateGCD(numArr);
    if (curNum % gcd === 0) answer++;
  }
  return answer;
}

function generateGCD(numArr) {
  let res = 1;
  for (let i = 2; i < 10; i++) {
    res = numArr.every((n) => n % i === 0) ? i : res;
  }
  return res;
}

长度为 n 的字符串 str 任意修改 k 个位置以后最长的相同字母连续子串。没想到滑动窗口

🔍 展开代码

2.js

const rl = require("readline").createInterface({ input: process.stdin });
const inputs = [];
rl.on("line", (line) => inputs.push(line));
rl.on("close", () => {
  const [n, k] = inputs[0].split(" ").map(Number);
  const str = inputs[1];
  console.log(deal(n, k, str));
});

function deal(n, k, str) {
  // 长度为 n 的字符串 str 任意修改 k 个位置以后最长的相同字母连续子串

  let maxLength = 0;

  // 对每个可能的字符（a-z）都尝试一次
  for (let targetChar = 0; targetChar < 26; targetChar++) {
    const char = String.fromCharCode(97 + targetChar); // 'a' + targetChar

    let left = 0,
      right = 0;
    let changesNeeded = 0;

    // 滑动窗口
    while (right < n) {
      // 扩展右边界
      if (str[right] !== char) {
        changesNeeded++;
      }

      // 收缩左边界，直到修改次数不超过k
      while (changesNeeded > k) {
        if (str[left] !== char) {
          changesNeeded--;
        }
        left++;
      }

      // 更新最大长度
      maxLength = Math.max(maxLength, right - left + 1);
      right++;
    }
  }

  return maxLength;
}

// 测试
console.log(deal(4, 2, "abcd")); // 3
console.log(deal(5, 2, "abacc")); // 4
console.log(deal(8, 1, "aaaacaaa")); // 8

给定一个数组 nums，nums 有多少个子序列在 Fibonacci 序列中。Claude 懵逼了

🔍 展开代码

3.js

const rl = require("readline").createInterface({ input: process.stdin });
const inputs = [];
rl.on("line", (line) => inputs.push(line));
rl.on("close", () => {
  for (let i = 1; i < inputs.length; i += 2) {
    const n = +inputs[i];
    const nums = inputs[i + 1].split(" ").map(Number);
    // nums 有多少个子序列在 Fibonacci 序列中
    console.log(deal(n, nums));
  }
});
function deal(n, nums) {}

console.log(deal(3, [1, 1, 1])); // 6 [1]*3 [1,1]*2
console.log(deal(4, [1, 1, 2, 3])); // 15
// [1]*2 [2]*1 [3]*1
// [1,1]*1 [1,2]*2 [1,3]*2 [2,3]*1
// [1,1,2]*1 [1,2,3]*2 [1,1,3]*1
// [1,1,2,3]*1

饿了么前端秋招笔试 ​

饿了么前端秋招笔试