360位数

给定数字N ，任务是找到^第N^个360角数字。

A 360-gon number is a class of figurate numbers. It has a 360-sided polygon called 360-gon. The N-th 360-gon number count’s the 360 number of dots and all other dots are surrounding with a common sharing corner and make a pattern. The first few 360-gon numbers are 1, 360, 1077, 2152, 3585, 5376, … 
 

例子：

Input: N = 2 
Output: 360 
Explanation: 
The second 360-gonol number is 360. 
Input: N = 3 
Output: 1077 
 

方法：第N个360-gon数由以下公式给出：

• 侧多边形的第N个项= $\frac{((s-2)n^2 - (s-4)n)}{2}$
• 因此360边多边形的第N个项是

$Tn =\frac{((360-2)n^2 - (360-4)n)}{2} =\frac{(358^2 - 356)}{2}$

下面是上述方法的实现：

C++

// C++ implementation for
// above approach
#include 
using namespace std;
 
// Function to find the
// nth 360-gon Number
int gonNum360(int n)
{
    return (358 * n * n - 356 * n) / 2;
}
 
// Driver Code
int main()
{
    int n = 3;
    cout << gonNum360(n);
 
    return 0;
}

Java

// Java program for above approach
class GFG{
 
// Function to find the
// nth 360-gon Number
static int gonNum360(int n)
{
    return (358 * n * n - 356 * n) / 2;
}
 
// Driver code
public static void main(String[] args)
{
    int n = 3;
    System.out.print(gonNum360(n));
}
}
 
// This code is contributed by shubham

Python3

# Python3 implementation for
# above approach
 
# Function to find the
# nth 360-gon Number
def gonNum360(n):
 
    return (358 * n * n - 356 * n) // 2;
 
# Driver Code
n = 3;
print(gonNum360(n));
 
# This code is contributed by Code_Mech

C#

// C# program for above approach
using System;
class GFG{
 
// Function to find the
// nth 360-gon Number
static int gonNum360(int n)
{
    return (358 * n * n - 356 * n) / 2;
}
 
// Driver code
public static void Main(String[] args)
{
    int n = 3;
    Console.Write(gonNum360(n));
}
}
 
// This code is contributed by sapnasingh4991

Javascript

 
// JavaScript implementation for
// above approach
 
// Function to find the
// nth 360-gon Number
function gonNum360(n)
{
    return (358 * n * n - 356 * n) / 2;
}
 
// Driver Code
var n = 3;
document.write(gonNum360(n));
 

输出：

1077

参考： https ： //en.wikipedia.org/wiki/360-gon