以下の配列の各数の出現回数を数えて出力してください
const list = [44, 38, 39, 44, 40, 45, 44, 34, 42, 30, 43, 37, 36, 43, 35, 30, 40, 43, 33, 31, 42, 32, 36, 49, 47, 30, 46, 33, 42, 41, 45, 38, 31, 32, 34, 33, 48, 31, 37, 42, 44, 46, 46, 42, 43, 39, 41, 34, 46, 47, 33, 33, 36, 39, 45, 36, 39, 42, 32, 31, 49, 39, 39, 32, 40, 39, 43, 35, 32, 31, 33, 40, 48, 47, 47, 43, 41, 48, 39, 43, 39, 48, 31, 30, 35, 41, 31, 36, 49, 39, 47, 48, 41, 47, 34, 43, 33, 49, 31, 32, 48, 36, 46, 41, 38, 35, 42, 42, 44, 39, 43, 46, 36, 35, 48, 38, 49, 38, 43, 37, 45, 47, 34, 36, 32, 42, 30, 45, 47, 49, 44, 34, 30, 38, 41, 42, 36, 38, 35, 43, 43, 33, 44, 43, 47, 49, 43, 31, 47, 33, 49, 32, 46, 35, 42, 44, 49, 49, 47, 44, 32, 49, 43, 49, 47, 47, 40, 38, 47, 45, 38, 31, 39, 47, 33, 46, 36, 30, 33, 37, 32, 43, 41, 43, 39, 31, 40, 31, 44, 36, 48, 42, 33, 48, 39, 35, 39, 35, 39, 45, 32, 30, 38, 36, 36, 32, 35, 46, 49, 35, 48, 43, 33, 47, 32, 41, 47, 47, 49, 35, 32, 43, 38, 47, 48, 34, 33, 42, 33, 30, 35, 30, 38, 39, 34, 43, 46, 34, 41, 40, 34, 49, 35, 48, 32, 39, 38, 45, 36, 35, 45, 36, 39, 40, 49, 49, 32, 37, 32, 49, 48, 31, 46, 42, 43, 41, 48, 34, 32, 48, 37, 46, 41, 36, 45, 43, 46, 42, 43, 41, 33, 34, 32, 43, 45, 35, 47, 41, 38, 45, 44, 46, 46, 36, 49, 41, 45, 43, 38, 30]
出力
30:11回 31:13回 32:19回 33:16回 34:12回 35:16回 36:17回 37:6回 38:15回 39:19回 40:8回 41:15回 42:15回 43:25回 44:11回 45:13回 46:15回 47:20回 48:15回 49:19回
解答例
const list = [44, 38, 39, 44, 40, 45, 44, 34, 42, 30, 43, 37, 36, 43, 35, 30, 40, 43, 33, 31, 42, 32, 36, 49, 47, 30, 46, 33, 42, 41, 45, 38, 31, 32, 34, 33, 48, 31, 37, 42, 44, 46, 46, 42, 43, 39, 41, 34, 46, 47, 33, 33, 36, 39, 45, 36, 39, 42, 32, 31, 49, 39, 39, 32, 40, 39, 43, 35, 32, 31, 33, 40, 48, 47, 47, 43, 41, 48, 39, 43, 39, 48, 31, 30, 35, 41, 31, 36, 49, 39, 47, 48, 41, 47, 34, 43, 33, 49, 31, 32, 48, 36, 46, 41, 38, 35, 42, 42, 44, 39, 43, 46, 36, 35, 48, 38, 49, 38, 43, 37, 45, 47, 34, 36, 32, 42, 30, 45, 47, 49, 44, 34, 30, 38, 41, 42, 36, 38, 35, 43, 43, 33, 44, 43, 47, 49, 43, 31, 47, 33, 49, 32, 46, 35, 42, 44, 49, 49, 47, 44, 32, 49, 43, 49, 47, 47, 40, 38, 47, 45, 38, 31, 39, 47, 33, 46, 36, 30, 33, 37, 32, 43, 41, 43, 39, 31, 40, 31, 44, 36, 48, 42, 33, 48, 39, 35, 39, 35, 39, 45, 32, 30, 38, 36, 36, 32, 35, 46, 49, 35, 48, 43, 33, 47, 32, 41, 47, 47, 49, 35, 32, 43, 38, 47, 48, 34, 33, 42, 33, 30, 35, 30, 38, 39, 34, 43, 46, 34, 41, 40, 34, 49, 35, 48, 32, 39, 38, 45, 36, 35, 45, 36, 39, 40, 49, 49, 32, 37, 32, 49, 48, 31, 46, 42, 43, 41, 48, 34, 32, 48, 37, 46, 41, 36, 45, 43, 46, 42, 43, 41, 33, 34, 32, 43, 45, 35, 47, 41, 38, 45, 44, 46, 46, 36, 49, 41, 45, 43, 38, 30]
const result = {}
for (let i = 0; i < list.length; i++) {
const num = list[i]
if (result[num] === undefined) {
result[num] = 0
}
result[num]++
}
for (let key in result) {
console.log(`${key}:${result[key]}回`)
}
