正多边形对角线长度
给定边长为 a 的正多边形。任务是找出对角线的长度。 例:
Input: a = 9, n = 10
Output: 17.119
Input: a = 4, n = 5
Output: 6.47213
接近 :
我们知道多边形内角之和=(n–2)* 180其中， n 是多边形的边数。 所以，每个内角=(n–2)* 180/n 现在，我们要找到 BC = 2 * x 。如果我们在 BC 上画一条垂线 AO ，我们会看到这条垂线将 BO 和 OC 中的 BC 一分为二，作为三角形 AOB 和 AOC 相互全等。 现在，t =(n–2)* 180/2n 所以， sint = x/a 因此， x = asint 因此，对角线=2x = 2 Sint = 2 asin((n–2)* 180/2n)
C++
// C++ Program to find the diagonal
// of a regular polygon with given side length
#include <bits/stdc++.h>
using namespace std;
// Function to find the diagonal
// of a regular polygon
float polydiagonal(float n, float a)
{
// Side and side length cannot be negative
if (a < 0 && n < 0)
return -1;
// diagonal
// degree converted to radians
return 2 * a * sin((((n - 2) * 180) / (2 * n)) * 3.14159 / 180);
}
// Driver code
int main()
{
float a = 9, n = 10;
cout << polydiagonal(n, a) << endl;
return 0;
}
Java 语言(一种计算机语言，尤用于创建网站)
// Java Program to find the diagonal
// of a regular polygon with given side length
class GFG {
// Function to find the diagonal
// of a regular polygon
static float polydiagonal(float n, float a) {
// Side and side length cannot be negative
if (a < 0 && n < 0) {
return -1;
}
// diagonal
// degree converted to radians
return (float) (2 * a * Math.sin((((n - 2) * 180) / (2 * n)) * 3.14159 / 180));
}
// Driver code
public static void main(String[] args) {
float a = 9, n = 10;
System.out.printf("%.3f",polydiagonal(n, a));
}
}
// This code is contributed by 29AjayKumar
Python 3
# Python3 Program to find the diagonal
# of a regular polygon with given side length
import math as mt
# Function to find the diagonal
# of a regular polygon
def polydiagonal(n, a):
# Side and side length cannot
# be negative
if (a < 0 and n < 0):
return -1
# diagonal degree converted to radians
return (2 * a * mt.sin((((n - 2) * 180) /
(2 * n)) * 3.14159 / 180))
# Driver code
a, n = 9, 10
print(polydiagonal(n, a))
# This code is contributed
# by Mohit kumar 29
C
// C# Program to find the diagonal
// of a regular polygon with given side length
using System;
public class GFG{
// Function to find the diagonal
// of a regular polygon
static float polydiagonal(float n, float a) {
// Side and side length cannot be negative
if (a < 0 && n < 0) {
return -1;
}
// diagonal
// degree converted to radians
return (float) (2 * a * Math.Sin((((n - 2) * 180) / (2 * n)) * 3.14159 / 180));
}
// Driver code
static public void Main (){
float a = 9, n = 10;
Console.WriteLine(polydiagonal(n, a));
}
}
// This code is contributed by @Sachin...
服务器端编程语言（Professional Hypertext Preprocessor 的缩写）
<?php
// PHP Program to find the diagonal of a
// regular polygon with given side length
// Function to find the diagonal
// of a regular polygon
function polydiagonal ($n, $a)
{
// Side and side length cannot
// be negative
if ($a < 0 && $n < 0)
return -1;
// diagonal
// degree converted to radians
return 2 * $a * sin(((($n - 2) * 180) /
(2 * $n)) * 3.14159 / 180);
}
// Driver code
$a = 9;
$n = 10;
echo polydiagonal($n, $a);
// This code is contributed
// by Sach_Code
?>
java 描述语言
<script>
// javascript Program to find the diagonal
// of a regular polygon with given side length
// Function to find the diagonal
// of a regular polygon
function polydiagonal(n , a) {
// Side and side length cannot be negative
if (a < 0 && n < 0) {
return -1;
}
// diagonal
// degree converted to radians
return (2 * a * Math.sin((((n - 2) * 180)
/ (2 * n)) * 3.14159 / 180));
}
// Driver code
var a = 9, n = 10;
document.write(polydiagonal(n, a).toFixed(3));
// This code contributed by Princi Singh
</script>
Output:
17.119
版权属于：月萌API www.moonapi.com，转载请注明出处
