Rectangle#8883

Rectangle (Editorial)

A rectangle can be formed only if the numbers $a, b, c, d$ a, b, c, d can be grouped into pairs of equal values. All possible pairings should be considered, namely:

$a = b$ a = b and $c = d$ c = d;
$a = c$ a = c and $b = d$ b = d;
$a = d$ a = d and $b = c$ b = c;

The task can also be solved using sorting. Let the array $m$ contain the four given integers. Sort the array. A rectangle can be formed from these numbers if and only if the condition $m [0] = m [1]$ m[0] = m[1] and $m [2] = m [3]$ m[2] = m[3] holds.

Algorithm implementation

Read the input data.

scanf("%lld %lld %lld %lld", &a, &b, &c, &d);

If the rectangle exists, print its perimeter.

if ((a == b && c == d) || (a == c && b == d) || (a == d && b == c))
  printf("%d\n", a + b + c + d);

Otherwise print "No".

else
  printf("No\n");

Algorithm implementation – sort

Declare an array to store the four input numbers.

int m[4];

Read the input data.

scanf("%d %d %d %d", &m[0], &m[1], &m[2], &m[3]);

Sort the numbers.

sort(m, m + 4);

If the rectangle exists, print its perimeter.

if (m[0] == m[1] && m[2] == m[3])
  printf("%d\n", m[0] + m[1] + m[2] + m[3]);

Otherwise print "No".

else
  printf("No\n");

Java implementation

import java.util.*;

public class Main
{
  public static void main(String[] args) 
  {
    Scanner con = new Scanner(System.in);
    int a = con.nextInt();
    int b = con.nextInt();
    int c = con.nextInt();
    int d = con.nextInt();
    
    if ((a == b && c == d) || (a == c && b == d) || 
        (a == d && b == c))
    	System.out.println(a + b + c + d);
    else
      System.out.println("No");
    con.close();
  }
}

Java

Python implementation

Read the input data.

a, b, c, d = map(int, input().split())

If the rectangle exists, print its perimeter.

if (a == b and c == d) or (a == c and b == d) or (a == d and b == c):
  print(a + b + c + d)

Otherwise print "No".

else:
  print("No")