## Algorithm

Problem Name: beecrowd | 2802

# Dividing Circles

By Francisco Elio Parente Arcos Filho, UEA Brazil

Timelimit: 1

Given a set of N points on a circumference of a circle, every pair of points is connected by a segment and three of those segments never cross each other in a point inside the circumference.

Your task is to determine in how many parts these segments divide the interior of the circle.

## Input

The first and only line of the input contains an integer N (1 ≤ N ≤ 1000) representing the number of points on the circumference.

## Output

The output consists of a single line containing an integer representing the number of parts of the circle.

 Input Samples Output Samples 1 1

 2 2

 3 4

 4 8

 5 16

## Code Examples

### #1 Code Example with C Programming

```Code - C Programming```

``````
#include <stdio.h>
#include <math.h>

int main() {
double N, resposta;

scanf("%lf", &N);
resposta = (pow(N, 4.0) - (6.0 * pow(N, 3.0)) + (23.0 * pow(N, 2.0)) - (18.0 * N) + 24.0 ) / 24.0;
printf("%.0lf\n", resposta);

return 0;
}
``````
Copy The Code &

Input

cmd
1

Output

cmd
1

### #2 Code Example with Javascript Programming

```Code - Javascript Programming```

``````
const { readFileSync } = require("node:fs")
.split("\n", 1)
.map(value => Number.parseInt(value, 10))

const R = (n = 0) => 1 + (n * (n - 1) * (12 + (n - 2) * (n - 3))) / 24

console.log(R(input))
``````
Copy The Code &

Input

cmd
1

Output

cmd
1

### #3 Code Example with Python Programming

```Code - Python Programming```

``````
n = int(input())
n = ((n/24.0)*(n*n*n - 6*n*n + 23*n - 18)) + 1
print("%.0f" % n)

``````
Copy The Code &

Input

cmd
1

Output

cmd
1