8883. Rectangle

You are given four positive integers a, b, c, d. Determine is it possible to form a rectangle with side lengths a, b, c, d. If such a rectangle exists, print the sum of all four numbers. Otherwise, print “No”.

Input. Four positive integers a, b, c, d, each not exceeding 10⁹.

Output. If the rectangle exists, print the sum of all numbers. Otherwise, print “No”.

Sample input 1	Sample output 1
7 4 4 7	22
Sample input 2	Sample output 2
9 9 9 6	No

SOLUTION

conditional statement

Algorithm analysis

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

· a = b and c = d;

· a = c and b = d;

· a = d and 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] and 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();

}

}

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")