問題
Models need numbers, not words. One-hot encoding turns each category into a vector with one position per category: 1 at the category's position and 0 everywhere else.
Order the categories alphabetically. For each label, output its one-hot vector.
Implement one_hot(labels).
Input
labels: A list of category names.
Output
Return a matrix with one row per label and one column per distinct category (alphabetical order).
制約
1 ≤ length ≤ 1,000
Each label is 1 to 20 characters
例
例 1
入力：
labels = ["red", "green", "blue", "green"]
期待される出力：
expected = [
[0, 0, 1],
[0, 1, 0],
[1, 0, 0],
[0, 1, 0]
]入力：
std::vector<std::string> labels = {"red", "green", "blue", "green"};
期待される出力：
std::vector<std::vector<long long>> expected = {
{0, 0, 1},
{0, 1, 0},
{1, 0, 0},
{0, 1, 0}
};入力：
string[] labels = new string[] {"red", "green", "blue", "green"};
期待される出力：
long[][] expected = new long[][] {
new long[] {0, 0, 1},
new long[] {0, 1, 0},
new long[] {1, 0, 0},
new long[] {0, 1, 0}
};解説
The categories in alphabetical order are blue, green, red. So red → [0, 0, 1], green → [0, 1, 0] and blue → [1, 0, 0].
例 2
入力：
labels = ["yes"]
期待される出力：
expected = [
[1]
]入力：
std::vector<std::string> labels = {"yes"};
期待される出力：
std::vector<std::vector<long long>> expected = {
{1}
};入力：
string[] labels = new string[] {"yes"};
期待される出力：
long[][] expected = new long[][] {
new long[] {1}
};解説
There is only one category, so every vector is [1].
参考資料
この課題はCodeUtility用に調整されています。上記の説明と制約に従ってください。