Pattern 8
Objective
Write a C++ program to print a Diamond pattern using stars.
Algorithm / Approach
- Use a master loop to build the top half of the diamond (a centered pyramid with
2*i - 1stars). - Use a second master loop to build the bottom half of the diamond (an inverted centered pyramid).
- Carefully align the spaces in both halves so the widest row matches seamlessly.
main.cpp
#include<iostream>
using namespace std;
int main() {
int n,i,j,k;
cout<<"Enter the value for N : ";
cin>>n;
for(i = 1; i<=n; i++) {
for(j = 0; j< n-i; j++) {
cout<<" ";
}
for(k=0; k< (2*i)-1; k++) {
cout<<"*";
}
cout<< endl;
}
for(i = 1; i< n;i++) {
for(j = 0; j< i; j++) {
cout<<" ";
}
for(k = 0; k< 2*(n-i)-1; k++) {
cout<<"*";
}
cout<< endl;
}
return 0;
}Expected Output
* *** ***** *** *
Explanation of the Program
- A diamond is just a standard upward-facing pyramid stacked on top of a downward-facing inverted pyramid.
- The formula
(2 * i) - 1is a standard mathematical trick used to generate a sequence of odd numbers (1, 3, 5, 7), which ensures the pyramid always has a single star at the very top center.
Complexity
Time Complexity
O(n^2)
Space Complexity
O(1)
