Pattern 8

Easy

Inverted centred pyramid

Problem

Print an inverted centred star pyramid 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 pyramid formulas run backwards: row i takes i-1 leading spaces and 2(n-i)+1 stars. Placing this directly under pattern 7 gives you the diamond.

←→stepspaceplay

rows5

1/7

Optimal

timeO(n^2)spaceO(1)

1// n = 5 produces:2// *********3//  *******4//   *****5//    ***6//     *7 8for i in 0..n-1:9  print ' ' x i10  print '*' x (2(n-i)-1)11  newline

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