Programming & Computer Science Answers

1.1 If we apply the cross-product operation to these two instances of STUDENTS & BOOKS, what would be the resulting relation? (15)

STUDENTS

Student_ID Student_Name Qualification

401 Andile HCIT

402 Carol DIT

403 Amber BSc

404 Bright HCIT

 BOOKS

Book_ID Title Copy-right

101 Database fundamentals 2017

102 C++ how to program 2018

103 Simply Visual Basic 2019

104 OOP for beginners 2020

1.2 SELECT and RETURN all students with qualification HCIT from relations STUDENTS X BOOKS. (10)

1.3 Write a relational algebra expression using the symbolic notation for the given question in (1.2)

above. (5)

In the shop there are 3 barbers, Alpha, Beta and Gamma, who are not always efficient as employees. All the customers are seated in a waiting area, each customer has a card which has a unique integral ID.Alpha: He will call either the person with least ID from the waiting area of the one with max ID. Min or Max is decided randomly by him (assume 50% probability for each min or max). Beta: He will choose a ‘k’ and will call the kth smallest ID, (Kth ID when all IDs are arranged in ascending order). K is chosen randomly from the number of persons available in waiting area (1<= K <= Total persons)

Gamma: He will always choose the median ID. If there are ‘n’ people in the waiting area, the median will be defined as (n+1)/2 th ID when all of them are arranged in ascending order. (For both odd and even ‘n’ ). design a data structure which should support the query of each of the three barbers.

Shaded Diamond Given an integer value N as input,write a program to print a shaded diamond of 2*N -1 rows using an asterisk(*) character as shown below.
Sample Input 1
6
Sample Output 1
     * 
    * * 
   * * * 
  * * * * 
 * * * * * 
* * * * * * 
 *       *
  *     *
   *   *
    * *
     *
Sample Input 2
5
Sample Output 2
    * 
   * * 
  * * * 
 * * * * 
* * * * * 
 *     *
  *   *
   * *
    *
this code not correct output:
N = int(input())
for ​i in range(1, N + 1):
    for j in range(1, N - i + 1):
        print(end = ' ')
    for l in range(1, 2 * i):
        if l == 1 or l == i * 2 - 1:
            print('*', end = '')
        else:
            print('*', end = '')
    print()
for ​i in range(N - 1, 0, -1):
    for j in range(1, N - i + 1):
        print(' ', end = '')
    for l in range(1, 2 * i):
    print()

Perfect Squares in a Range

You are given two given numbers, A and B where 1 <= A <= B, Write a program to find the number of perfect squares in the range A to B (including A and B).

Input

The first line of input is an integer A. The second line of input is an integer B.

Explanation

In the given example,

A = 9 and B = 100. The perfect squares in the range A to B are

3 * 3 = 9

4 * 4 = 16

5 * 5 = 25

6 * 6 = 36

7 * 7 = 49

8 * 8 = 64

9 * 9 = 81

10 * 10 = 100

So, the output should be

8.

Sample Input 1

9

100

Sample Output 1

8

Sample Input 2

625

1444

Sample Output 2

14

Sum of 1 series

Given integer N as input. Write a program to print the sum of series 1 + 11 + 111 + .... N terms.

Input

The first line of input is an integer N.

Output

The output should be an integer representing the sum of series.

Explanation

Given

N = 4The sum for first

4 terms is 1 + 11 + 111 + 1111So the output should be

1234.

Sample Input 1

4

Sample Output 1

1234

Sample Input 2

5

Sample Output 2

12345

Number of digits until N

Given an integer N, write a program that prints the count of the total number of digits between 1 and N.

Input

The input is a positive integer.

Output

The output should be a single line containing the count of the digits up to the given number.

Explanation

Given

N = 10From 1 to 9, each number contains a single digit. From 10 onwards, the numbers contain two digits.

So the output should be 9 + 2 =

11.

Sample Input 1

10

Sample Output 1

11

Sample Input 2

4

Sample Output 2

4

Sum of K powers

Write a program to print the sum of the Kth power of the first N natural numbers.

Input

The first line of input is an integer N. The second line of input is an integer K.

Explanation

In the given example, the sum of first

5 natural numbers power of 3.The sum should be 1³ + 2³ + 3³ + 4³ + 5³

Therefore, the output should be

225.

Sample Input 1

5

3

Sample Output 1

225

Sample Input 2

2

8

Sample Output 2

257

Diamond Crystal

Given an integer value 

N, write a program to print a diamond pattern of 2*N rows as shown below.

Input

The first line of input is an integer 

N.

Explanation

In the given example, the number of rows in the diamond is 

2*5 = 10.

So, the output should be

    /\
   /  \
  /    \
 /      \
/        \
\        /
 \      /
  \    /
   \  / 
    \/
Sample Input 1
5
Sample Output 1
    /\
   /  \
  /    \
 /      \
/        \
\        /
 \      /
  \    /
   \  /
    \/
Sample Input 2
3
Sample Output 2
  /\
 /  \
/    \
\    /
 \  /
  \/

please provide correct output

Diamond

Given an integer value 

N, write a program to print a number diamond of 2*N -1 rows as shown below.

Input

The first line of input is an integer 

N.

Explanation

In the given example, the number of rows in the diamond is 

5.

So, the output should be

. . . . 0 . . . . 
. . . 0 0 0 . . . 
. . 0 0 0 0 0 . . 
. 0 0 0 0 0 0 0 . 
0 0 0 0 0 0 0 0 0
. 0 0 0 0 0 0 0 . 
. . 0 0 0 0 0 . . 
. . . 0 0 0 . . . 
. . . . 0 . . . .
Sample Input 1
5
Sample Output 1
. . . . 0 . . . . 
. . . 0 0 0 . . . 
. . 0 0 0 0 0 . . 
. 0 0 0 0 0 0 0 . 
0 0 0 0 0 0 0 0 0 
. 0 0 0 0 0 0 0 . 
. . 0 0 0 0 0 . . 
. . . 0 0 0 . . . 
. . . . 0 . . . .
Sample Input 2
4
Sample Output 2
. . . 0 . . . 
. . 0 0 0 . . 
. 0 0 0 0 0 . 
0 0 0 0 0 0 0 
. 0 0 0 0 0 . 
. . 0 0 0 . . 
. . . 0 . . .

please provide correct output