谁拥有最多的钱 - Codewars 挑战 - JavaScript

Question

You're going on a trip with some students and it's up to you to keep track of how much money each Student has. A student is defined like this:

class Student {
  constructor(name, fives, tens, twenties) {
    this.name = name;
    this.fives = fives;
    this.tens = tens;
    this.twenties = twenties;
  }
}

As you can tell, each Student has some fives, tens, and twenties. Your job is to return the name of the student with the most money. If every student has the same amount, then return "all".

Notes:

Each student will have a unique name

There will always be a clear winner: either one person has the most, or everyone has the same amount

If there is only one student, then that student has the most money

我试过这个：

function mostMoney(students) {
  //get array of totals
  let array = [];
  students.forEach((value, index) => {
     let total = ((5 * value.fives) + (10 * value.tens) + (20 * value.twenties));
     array.push([total, value.name]);
  });
  //sort array of totals
  array = array.sort((a, b) => b[0] - a[0]);
  console.log('array****', array);
  //check if all totals are equal - if they are, return 'all'
  if (array.every((el, i, array) => (el)[0]) === array[0][0]) {
    return 'all'; 
  }
  else {
    return array[0][1];
  }
}

对我来说没有意义的是，当我在 codewars 中 console.log('array****', array); 时，它看起来像：

array**** [ [ 50, 'Eric' ],
  [ 40, 'Andy' ],
  [ 40, 'Stephen' ],
  [ 40, 'Phil' ],
  [ 30, 'David' ] ]
array**** [ [ 50, 'Eric' ],
  [ 40, 'Andy' ],
  [ 40, 'Stephen' ],
  [ 40, 'Phil' ],
  [ 30, 'Cameron' ],
  [ 30, 'Geoff' ],
  [ 30, 'David' ] ]
array**** [ [ 40, 'Andy' ] ]
array**** [ [ 40, 'Stephen' ] ]
array**** [ [ 30, 'Cameron' ], [ 30, 'Geoff' ] ]

为什么看起来像那样？我认为排序后，我的 console.log('array***', array) 应该看起来像：

array**** [ [ 50, 'Eric' ],
  [ 40, 'Andy' ],
  [ 40, 'Stephen' ],
  [ 40, 'Phil' ],
  [ 30, 'Cameron' ],
  [ 30, 'Geoff' ],
  [ 30, 'David' ] ]

当我最初console.log(students)时，它看起来像一个数组：

[ Student { name: 'Andy', fives: 0, tens: 0, twenties: 2 },
  Student { name: 'Stephen', fives: 0, tens: 4, twenties: 0 },
  Student { name: 'Eric', fives: 8, tens: 1, twenties: 0 },
  Student { name: 'David', fives: 2, tens: 0, twenties: 1 },
  Student { name: 'Phil', fives: 0, tens: 2, twenties: 1 } ]

所以我试图用我的 forEach 循环收集数组中的所有总数，然后在循环后对该数组进行排序 - 这个逻辑有什么问题？

Answer 1

工作解决方案:)

function mostMoney(students) {
  let array = [];
  if (students.length === 1) {
     return students[0].name;
  }
  students.forEach((value, index) => {
     let total = ((5 * value.fives) + (10 * value.tens) + (20 * value.twenties));
     array.push([total, value.name]);
  });
  array = array.sort((a, b) => b[0] - a[0]);
  if (array.every((el, i, array) => el[0] === array[0][0])) {
    return 'all'; 
  }
  else {
    return array[0][1];
  }
}

实际上我的 .every 有问题 - 我正在做 (el)[0]) 而不是 el[0]，然后我也没有正确检查何时只有一个学生进入 mostMoney。

感谢大家阐明 console.log 问题。 Codewars console.log 进行了多次测试，因为正如你们所说，它是运行多次测试。

Answer 2

我可以建议解决方案：

  function mostMoney(students) {
     //deep copy of argument
     let input = [...students];
     // sort students by total descending
     let sum = st => st.fives * 5 + st.tens * 10 + st.twenties * 20;
     let comparator = (st1,st2) => sum(st2) - sum(st1);
     input.sort(comparator);     
     // result
     //just compare the first two students
     if(input.length >=2 && sum(input[0]) == sum(input[1])){
      return 'all';
     }
     else{
      return input[0].name;
     }
  }

谁拥有最多的钱 - Codewars 挑战 - JavaScript

Who Has the Most Money - Codewars Challenge - JavaScript

javascript

arrays

class

instance