Program to print half Diamond star pattern
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 then 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 =
Below is the implementation of the above approach:
C++
// C++ implementation to print the
// half diamond star pattern
#include <iostream>
using
namespace
std;
// Function to print the
// half diamond star pattern
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++)
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 Code
int
main()
{
int
N = 5;
// Function Call
halfDiamondStar(N);
}
Java
// Java implementation to print the
// half diamond star pattern
import
java.util.*;
class
GFG{
// Function to print the
// half diamond star pattern
static
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 Code
public
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 pattern
def
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 Code
N
=
5
;
# Function Call
halfDiamondStar(N);
# This code is contributed by skylags
C#
// C# implementation to print the
// half diamond star pattern
using
System;
class
GFG{
// Function to print the
// half diamond star pattern
static
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 Code
public
static
void
Main(String[] args)
{
int
N = 5;
// Function Call
halfDiamondStar(N);
}
}
// This code is contributed by Rohit_ranjan
Output:* ** *** **** ***** **** *** ** *
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