Given an integer N, the task is to print half-diamond-star pattern.
*
**
***
****
*****
******
*****
****
***
**
*
Examples:
Input: N = 3 Output: * ** *** ** * Input: N = 6 Output: * ** *** **** ***** ****** ***** **** *** ** *
Approach: The idea is to break the pattern into two halves that is upper half and lower half. Then print them separately with the help of the loops. The key observation for printing the upper half and lower half is described as below:
- Upper half: The upper half of the pattern contains star ‘*’ in increasing order where ith line contains following number of star:
Number of '*' in ith line =
- Lower Half: The lower half of the pattern contains star ‘*’ in decreasing order where ith line contains following number of star:
Number of '*' in ith line =
C++
// C++ implementation to print the// half diamond star pattern #include <iostream> using namespace std; // Function to print the// half diamond star patternvoid halfDiamondStar(int N){ int i, j; // Loop to print the upper half // diamond pattern for (i = 0; i < N; i++) { for (j = 0; j < i + 1; j++) cout << "*"; cout << "\n"; } // Loop to print the lower half // diamond pattern for (i = 1; i < N; i++) { for (j = i; j < N; j++) cout << "*"; cout << "\n"; }} // Driver Codeint main(){ int N = 5; // Function Call halfDiamondStar(N);} |
Java
// Java implementation to print the// half diamond star patternimport java.util.*; class GFG{ // Function to print the// half diamond star patternstatic void halfDiamondStar(int N){ int i, j; // Loop to print the upper half // diamond pattern for (i = 0; i < N; i++) { for (j = 0; j < i + 1; j++) System.out.print("*"); System.out.print("\n"); } // Loop to print the lower half // diamond pattern for (i = 1; i < N; i++) { for (j = i; j < N; j++) System.out.print("*"); System.out.print("\n"); }} // Driver Codepublic static void main(String[] args){ int N = 5; // Function Call halfDiamondStar(N);}} // This code is contributed by Rohit_ranjan |
Python3
# Python3 implementation to print the# half diamond star pattern # Function to print the# half diamond star patterndef halfDiamondStar(N): # Loop to print the upper half # diamond pattern for i in range(N): for j in range(0, i + 1): print("*", end = "") print() # Loop to print the lower half # diamond pattern for i in range(1, N): for j in range(i, N): print("*", end = "") print() # Driver CodeN = 5; # Function CallhalfDiamondStar(N); # This code is contributed by skylags |
C#
// C# implementation to print the// half diamond star patternusing System; class GFG{ // Function to print the// half diamond star patternstatic void halfDiamondStar(int N){ int i, j; // Loop to print the upper half // diamond pattern for(i = 0; i < N; i++) { for(j = 0; j < i + 1; j++) Console.Write("*"); Console.Write("\n"); } // Loop to print the lower half // diamond pattern for(i = 1; i < N; i++) { for(j = i; j < N; j++) Console.Write("*"); Console.Write("\n"); }} // Driver Codepublic static void Main(String[] args){ int N = 5; // Function Call halfDiamondStar(N);}} // This code is contributed by Rohit_ranjan |
Javascript
// JavaScript implementation to print the// half diamond star pattern // Function to print the// half diamond star patternfunction halfDiamondStar(N){ let i, j; // Loop to print the upper half // diamond pattern for (i = 0; i < N; i++) { for (j = 0; j < i + 1; j++) console.log("*"); console.log("<br>"); console.log("\n"); } // Loop to print the lower half // diamond pattern for (i = 1; i < N; i++) { for (j = i; j < N; j++) console.log("*"); console.log("<br>"); console.log("\n"); } } // Driver Code let N = 5; // Function Call halfDiamondStar(N); |
Output
* ** *** **** ***** **** *** ** *
Time complexity: O(N2) where N is given integer
Auxiliary Space: O(1)
