lecture # 5 : building logic through presudo code

before proceeding let me tell you some hard facts about computer

algorithm aren't computer codes so your style to demonstrate yor logic
computer deals with finite things
which means whole numbers and numbers never lie

computer is a device that takes input process it and gives out-come

outcome must be desired one (required one)

now we would see some algorihms

Write an algorithm to add two numbers entered by user.

Step 1: Start

Step 2: Declare variables num1, num2 and sum.

Step 3: Read values num1 and num2.

Step 4: Add num1 and num2 and assign the result to sum.

        sum←num1+num2

Step 5: Display sum

Step 6: Stop

Write an algorithm to find the largest among three different numbers entered by user.

Step 1: Start

Step 2: Declare variables a,b and c.

Step 3: Read variables a,b and c.

Step 4: If a>b

           If a>c

              Display a is the largest number.

           Else

              Display c is the largest number.

        Else

           If b>c

              Display b is the largest number.

           Else

              Display c is the greatest number. 

Step 5: Stop

Write an algorithm to find all roots of a quadratic equation ax2+bx+c=0.

Step 1: Start

Step 2: Declare variables a, b, c, D, x1, x2, rp and ip;

Step 3: Calculate discriminant

         D←b2-4ac

Step 4: If D≥0

              r1←(-b+√D)/2a

              r2←(-b-√D)/2a

              Display r1 and r2 as roots.

        Else    

              Calculate real part and imaginary part

              rp←b/2a

              ip←√(-D)/2a

              Display rp+j(ip) and rp-j(ip) as roots

Step 5: Stop      

      

Write an algorithm to find the factorial of a number entered by user.

Step 1: Start

Step 2: Declare variables n,factorial and i.

Step 3: Initialize variables

          factorial←1

          i←1

Step 4: Read value of n

Step 5: Repeat the steps until i=n

     5.1: factorial←factorial*i

     5.2: i←i+1

Step 6: Display factorial

Step 7: Stop

Write an algorithm to check whether a number entered by user is prime or not.

Step 1: Start

Step 2: Declare variables n,i,flag.

Step 3: Initialize variables

        flag←1

        i←2 

Step 4: Read n from user.

Step 5: Repeat the steps until i<(n/2)

     5.1 If remainder of n÷i equals 0

            flag←0

            Go to step 6

     5.2 i←i+1

Step 6: If flag=0

           Display n is not prime

        else

           Display n is prime

Step 7: Stop

Write an algorithm to find the Fibonacci series till term≤1000.

Step 1: Start

Step 2: Declare variables first_term,second_term and temp.

Step 3: Initialize variables first_term←0 second_term←1

Step 4: Display first_term and second_term

Step 5: Repeat the steps until second_term≤1000

     5.1: temp←second_term

     5.2: second_term←second_term+first term

     5.3: first_term←temp

     5.4: Display second_term

Step 6: Stop