C++ Program To Print The Diamond Shape

Last Updated : 25 Jan, 2023

Given a number n, write a program to print a diamond shape with 2n-1 rows.
Examples :

Input: 5
Output:

C++

// C++ program to print diamond shape
// with 2n-1 rows 
#include <bits/stdc++.h>
using namespace std;

// Prints diamond pattern with 2n-1 rows 
void printDiamond(int n) 
{ 
    int space = n - 1; 

    // run loop (parent loop) 
    // till number of rows 
    for (int i = 0; i < n; i++) 
    { 
        // loop for initially space, 
        // before star printing 
        for (int j = 0;j < space; j++) 
            cout << " "; 

        // Print i+1 stars 
        for (int j = 0; j <= i; j++) 
            cout << "* "; 

        cout << endl; 
        space--; 
    } 

    // Repeat again in reverse order 
    space = 0; 

    // run loop (parent loop) 
    // till number of rows 
    for (int i = n-1; i > 0; i--) 
    { 
        // loop for initially space, 
        // before star printing 
        for (int j = 0; j < space; j++) 
            cout << " "; 

        // Print i stars 
        for (int j = 0;j < i;j++) 
            cout << " *";

        cout << endl;
        space++; 
    } 
} 

// Driver code 
int main() 
{ 
    printDiamond(5); 
    return 0; 
} 

// This is code is contributed
// by rathbhupendra

Output

    * 
   * * 
  * * * 
 * * * * 
* * * * * 
 * * * *
  * * *
   * *
    *

Time Complexity: O(n*n) since we are traversing rows and columns of a grid for printing spaces ' ' and star '*'.
Auxiliary Space: O(1), No extra space used.