nested for structures

ahmed sami

Write a program that prints the following diamond shape. You may use output statements that print a single asterisk (*), a single space or a single newline character. Maximize your use of repetition (with nested for structures) and minimize the number of output statements.

***

*****

*******

*********

*******

*****

***

4 Replies

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Vulpes14y ago
Accepted answer
Try this:

using System;

class Diamond
{
static void Main()
{
for(int row = 0; row < 5; row++)
{
for(int col = 0; col < 4 - row; col++) Console.Write(" ");
for(int col = 0; col < 2 * row + 1; col++) Console.Write("*");
Console.Write("\n");
}

for(int row = 0; row < 4; row++)
{
for(int col = 0; col < row + 1; col++) Console.Write(" ");
for(int col = 0; col < 7 - 2 * row; col++) Console.Write("*");
Console.Write("\n");
}

Console.ReadKey();
}
}
ahmed sami14y ago
oh my god !!!
you are a Genius !!
thank you very much ..
^_^
Vulpes14y ago
This part of the code prints the first 5 rows of the diamond:

for(int row = 0; row < 5; row++)
{
for(int col = 0; col < 4 - row; col++) Console.Write(" ");
for(int col = 0; col < 2 * row + 1; col++) Console.Write("*");
Console.Write("\n");
}

Each row will begin with (4 - row) spaces followed by (2 * row + 1) asterisks and a new line character

So:

row 0 -> 4 spaces + 1 asterisk + '\n'
row 1 -> 3 spaces + 3 asterisks + '\n'
row 2 -> 2 spaces + 5 asterisks + '\n'
row 3 -> 1 space + 7 asterisks + '\n'
row 4 -> 0 spaces + 9 asterisks + '\n'

This part of the code then prints the last 4 rows of the diamond:

for(int row = 0; row < 4; row++)
{
for(int col = 0; col < row + 1; col++) Console.Write(" ");
for(int col = 0; col < 7 - 2 * row; col++) Console.Write("*");
Console.Write("\n");
}

Each row will begin with (row + 1) spaces followed by (7 - 2 * row) asterisks and a new line character.

So:

row 0 ( = row 5) -> 1 space + 7 asterisk + '\n'
row 1 ( = row 6) -> 2 spaces + 5 asterisks + '\n'
row 2 ( = row 7) -> 3 spaces + 3 asterisks + '\n'
row 3 ( = row 8) -> 4 spaces + 1 asterisks + '\n'

There are some fancier ways of doing this but this one is (fairly) easy to understand :)
ahmed sami14y ago
it works !!!
thank you ..
but can you explain the code please ?
couse i misunderstand it !!!