AlgoViz

Pattern 1

Easy

Solid n x n square

Problem

Print a solid n x n square of stars for a given size n.

In simple words

Use one loop for the rows and another for what goes in each row to draw the shape.

The idea

Two nested loops: the outer one picks a row, the inner one prints the characters of that row. Every pattern in this set is the same skeleton — only the inner loop's bounds and the character it prints change.

The trick

  • Outer loop = rows, inner loop = columns. Fix that and the rest is arithmetic.
  • Print the newline once per outer iteration, after the inner loop finishes.
rows5

Step 1 of 7. Solid square: every row prints n stars. rows 5.

1/7
Optimal
timeO(n^2)spaceO(1)
1// n = 5 produces:2// * * * * *3// * * * * *4// * * * * *5// * * * * *6// * * * * *7 8for i in 1..n:9  for j in 1..n: print('* ')10  newline

Input

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:
★ ★ ★ ★ ★ / ★ ★ ★ ★ ★ / ★ ★ ★ ★ ★ / ★ ★ ★ ★ ★ / ★ ★ ★ ★ ★

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