A diamond pattern in C++ can be printed by combining increasing and decreasing star patterns using nested loops. The pattern is formed by controlling the number of spaces and stars in each row.
- The upper half increases the number of stars from 1 to n.
- The lower half decreases the number of stars from n - 1 to 1.
Illustration
Input: 5
Output:
C++ Program to Print the Diamond Shape
#include <iostream>
using namespace std;
void printDiamond(int n)
{
// Print the upper half
for (int i = 1; i <= n; i++)
{
// Print leading spaces
for (int j = 1; j <= n - i; j++)
cout << " ";
// Print stars
for (int j = 1; j <= i; j++)
cout << "* ";
cout << endl;
}
// Print the lower half
for (int i = n - 1; i >= 1; i--)
{
// Print leading spaces
for (int j = 1; j <= n - i; j++)
cout << " ";
// Print stars
for (int j = 1; j <= i; j++)
cout << "* ";
cout << endl;
}
}
int main()
{
int n = 5;
printDiamond(n);
return 0;
}
Output
*
* *
* * *
* * * *
* * * * *
* * * *
* * *
* *
*Explanation: For n = 5, the upper half prints 1, 2, 3, 4, and 5 stars. The lower half then prints 4, 3, 2, and 1 stars. For each row, the number of leading spaces is n - i, which shifts the stars toward the center and produces the diamond shape.