Intermediate · Nested loops · 117 of 264
Pyramid
Print a pyramid of stars n rows high. Row i (from 1) has 2i - 1 stars, centred with spaces on the left only.
Input: n. Output: the pyramid.
Examples
Input
3
Output
* *** *****
Input
1
Output
*
One more test checks other inputs when you press Check.
Stuck? The idea behind nested loops
A loop inside a loop: for each turn of the outer loop, the inner one runs all the way through. Good for rows and columns.
print(..., end="") stays on the same line; an empty print() after the inner loop moves to the next row.
for row in range(1, 4):
line = []
for col in range(1, 4):
line.append(str(row * col))
print(" ".join(line))Watch for: print(x, end=" ") leaves a space at the end of every line, and the tests see it. Build each line as a list and print " ".join(line): spaces only between.