Pattern 6
EasyInverted number triangle
Problem
Print an inverted number triangle for a given size n.
Use one loop for the rows and another for what goes in each row to draw the shape.
The idea
The inverted triangle shape with the column counter printed instead of a star. Shape and content stay independent: pick the bound for the shape, pick the printed value for the content.
The trick
- Row i prints 1..(n-i+1).
rows5
Step 1 of 7. Inverted number triangle: row i prints 1..(n-i+1). rows 5.
1/7
Optimal
timeO(n^2)spaceO(1)
1// n = 5 produces:2// 1 2 3 4 53// 1 2 3 44// 1 2 35// 1 26// 17 8for i in 1..n:9 for j in 1..(n-i+1): print(j)10 newlineInput
- grid
- 5 × 5
Memory
- rows
- 5
Output
- printed rows
- —
- rows
- 5
Check yourself
3 quick questions about this walkthrough. A wrong answer costs nothing.
Example
- Input:
- n = 5
- Output:
- 1 2 3 4 5 / 1 2 3 4 / 1 2 3 / 1 2 / 1
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