Pyramid Rows

問題

Draw a right-aligned pyramid like the one in Super Mario: row i (counting from 1) has height − i spaces followed by i # characters.

Implement pyramid_rows(height).

height: The number of rows.

Return the rows from top to bottom.

0 ≤ height ≤ 50

例 1

入力：
height = 3

期待される出力：
expected = ["  #", " ##", "###"]

入力：
long long height = 3;

期待される出力：
std::vector<std::string> expected = {"  #", " ##", "###"};

入力：
long height = 3;

期待される出力：
string[] expected = new string[] {"  #", " ##", "###"};

Rows are " #", " ##" and "###": each row has one more block and one less space.

例 2

入力：
height = 1

期待される出力：
expected = ["#"]

入力：
long long height = 1;

期待される出力：
std::vector<std::string> expected = {"#"};

入力：
long height = 1;

期待される出力：
string[] expected = new string[] {"#"};

A single row with one block: "#".

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

Each row combines leading spaces with a growing run of hash characters.

ヒント 2

Build rows one by one from top to bottom so the alignment stays correct.

ヒント 3

If the height is zero, return no rows rather than an empty-looking pyramid.

目安の計算量

O(height^2) time, O(height^2) extra space

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。