Assume that an array of integers named a that contains exactly five elements has been declared and initialized. write a single statement that assigns a new value to the first element of the array. this new value should be equal to twice the value stored in the last element of the array.

In any programming language, the assignment statement is written as shown.

a[0] = 2*a[4];

Explanation:

This scenario is explained in c++ language.

An array is declared as follows.

Datatype array_name[length];

The variable length denotes the number of elements in the array. It is also an integer variable.

An element in the array is written as arr[k], where value of k ranges from 0 to ( length-1 ).

The first element is written as array_name[0], second element is written as array_name[1], and so on.

The elements in the array are initialized as shown.

array_name[0] = value1;

array_name[1] = value2;

For the given scenario, an integer array a is declared.

The variable length will be initialized to 5, which means the array a has exactly 5 elements.

int length = 5;

int a[length];

The elements of array a are initialized as shown.

a[0] = 1;

a[1] = 2;

a[2] = 3;

a[3] = 4;

a[4] = 5;

As per the given scenario, the first element of the array, a[0], needs to be assigned a new value. This new value is twice the value of the last element of the array, a[4].

The assignment statement is written as shown.

a[0] = ( 2 * a[4]) ;

The above statement assigns twice the value of the last element to the first element.

Thus, after the above statement is executed, the old value of a[0] which is 1 is over written.

Now, a[0] will hold new value which is

( 2 * a[4] )

= ( 2 * 5 )

= 10.

The value of the first element, a[0], is changed from 1 to 10.

The above can be programmed as shown.

#include <iostream>

using namespace std;

int main() {

   int length = 5;

   int a[length];    

   a[0] = 1;

   a[1] = 2;

   a[2] = 3;

   a[3] = 4;

   a[4] = 5;

   a[0] = (2*a[4]) ;

  return 0;      

}