問題
Splitting data into fixed-size chunks is how programs page results, batch database writes or send data in packets.
Given a list and a chunk size, cut the list into consecutive chunks of exactly size values, in order. The last chunk holds whatever is left and may be shorter.
Implement split_into_chunks(values, size).
Input
values: The list to split.
size: The chunk size.
Output
Return the list of chunks. An empty list gives no chunks.
制約
0 ≤ number of values ≤ 10,000
1 ≤ size ≤ 10,000
例
入力：
size = 3
values = [1, 2, 3, 4, 5, 6, 7]
期待される出力：
expected = [
[1, 2, 3],
[4, 5, 6],
[7]
]入力：
long long size = 3;
std::vector<long long> values = {1, 2, 3, 4, 5, 6, 7};
期待される出力：
std::vector<std::vector<long long>> expected = {
{1, 2, 3},
{4, 5, 6},
{7}
};入力：
long size = 3;
long[] values = new long[] {1, 2, 3, 4, 5, 6, 7};
期待される出力：
long[][] expected = new long[][] {
new long[] {1, 2, 3},
new long[] {4, 5, 6},
new long[] {7}
};解説
Groups of 3: [1, 2, 3] and [4, 5, 6], and the leftover 7 forms a last, shorter chunk.
入力：
size = 5
values = [8, 9]
期待される出力：
expected = [
[8, 9]
]入力：
long long size = 5;
std::vector<long long> values = {8, 9};
期待される出力：
std::vector<std::vector<long long>> expected = {
{8, 9}
};入力：
long size = 5;
long[] values = new long[] {8, 9};
期待される出力：
long[][] expected = new long[][] {
new long[] {8, 9}
};解説
The size is larger than the list, so everything fits in one chunk: [[8, 9]].
解き方のヒント
まずは自分で考えてから、ヒントを 1 つずつ開いてみましょう。
ヒント 1
Start positions are 0, size, 2·size, and so on.
ヒント 2
Take a slice from each start position up to start + size.
ヒント 3
The last slice may be shorter, and an empty list gives no chunks at all.
目安の計算量
O(n) time, O(n) extra space
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。