js出现次数最多

function countOccurrences(arr) {
  let counts = {};
  arr.forEach(function(x) { counts[x] = (counts[x] || 0) + 1; });
  return counts;
}

let arr = ['apple', 'banana', 'apple', 'orange', 'banana', 'apple'];
console.log(countOccurrences(arr)); // { apple: 3, banana: 2, orange: 1 }

function countOccurrences(arr) {
  let counts = new Map();
  arr.forEach(function(x) {
    counts.set(x, (counts.get(x) || 0) + 1);
  });
  return counts;
}

let arr = ['apple', 'banana', 'apple', 'orange', 'banana', 'apple'];
console.log(countOccurrences(arr)); // Map { 'apple' => 3, 'banana' => 2, 'orange' => 1 }

function findMostFrequent(arr) {
  let counts = {};
  arr.forEach(function(x) { counts[x] = (counts[x] || 0) + 1; });

  let maxCount = 0, mostFrequent;
  for (let key in counts) {
    if (counts[key] > maxCount) {
      maxCount = counts[key];
      mostFrequent = key;
    }
  }
  return { mostFrequent, maxCount };
}

let arr = ['apple', 'banana', 'apple', 'orange', 'banana', 'apple'];
console.log(findMostFrequent(arr)); // { mostFrequent: 'apple', maxCount: 3 }