Approach to Create Diamond Star Pattern
- The approach to creating a diamond star pattern will use 2 JavaScript Nested For loops to print the upper and lower half of the diamond.
- We will iterate from 1 to N and back to 1 to cover the diamond structure for input N.
- The nested loop will be used to create the string that contains the row to be printed each time with the condition of diamond that row+column > N and N+row < column.
- Print the resultant string each time using the console.log() method that adds a new line at the end of the output the form the required structure.
Example 1: Solid Diamond Start Pattern
Javascript
let n = 5; for (let i = 1; i <= n; i++) { let str = "*"; let space = ' '; console.log(space.repeat((n - i)) + str.repeat(i * 2 - 1)); } for (let i = n - 1; i >= 1; i--) { let str = "*"; let space = ' '; console.log(space.repeat((n - i)) + str.repeat(i * 2 - 1)); } |
Output
*
***
*****
*******
*********
*******
*****
***
*
Example 2: Hollow Diamond Star Pattern
Javascript
let n = 5; for (let i = 1; i <= n; i++) { let str = '' for (let j = 1; j <= 2 * n; ++j) { if (i + j == n + 1 || (i == j - n + 1)) { str += '*' } else str += ' ' } console.log(str); } for (let i = n - 1; i >= 1; i--) { let str = '' for (let j = 1; j <= 2 * n; ++j) { if (i + j == n + 1 || (i == j - n + 1)) str += '*' else str += ' ' } console.log(str); } |
Output
*
* *
* *
* *
* *
* *
* *
* *
*
Example 3: Inverted Hollow Diamond Pattern
Javascript
let n = 5; for (let i = 1; i <= n; i++) { let str = '' for (let j = 1; j < 2 * n; ++j) { if (i + j > n + 1 && (i > j - n + 1)) str += ' '; else str += '*'; } console.log(str); } for (let i = n - 1; i >= 1; i--) { let str = '' for (let j = 1; j < 2 * n; ++j) { if (i + j > n + 1 && (i > j - n + 1)) str += ' '; else str += '*'; } console.log(str); } |
Output
********* **** **** *** *** ** ** * * ** ** *** *** **** **** *********
JavaScript Program to Print Diamond Shape Star Pattern
This article will demonstrate how to create the diamond start pattern in JavaScript.