Page 108 - Computer science 868 Class 12
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Step 3: Calculate discriminant d = sqrt (b × b - 4 × a × c).
Step 4: If d < 0 then print roots are imaginary, go to Step 12.
Step 5: If d = 0 then print roots are real and equal, go to Step 6 else go to Step 8.
Step 6: Calculate r1 = -b/(2 x a).
Step 7: Print “Roots are”, r1 and go to Step 12.
Step 8: Calculate first root r1 = (-b + d)/(2 × a).
Step 9: Calculate second root r2 = (-b - d)/(2 × a).
Step 10: Print “Roots are real and unequal”.
Step 11: Print r1 and r2.
Step 12: Stop.
Problem 3: Write an algorithm to enter distance travelled by a cab and calculate fare as follows:
Distance travelled Fare
up to 1 km `30
Next 5 km `10 per km
Next 10 km `8 per km
Beyond 16 km `6 per km
Step 1: Start.
Step 2: Accept distance d.
Step 3: If d<=1 then fare f=30, go to Step 7.
Step 4: If d<=6 then f=30+(d-1)×10, go to Step 7.
Step 5: If d<=16 then f=30+5×10+(d-6)×8, go to Step 7.
Step 6: f=30+5×10+8×10+(d-16)×6.
Step 7: Print f.
Step 8: Stop.
3.5.2 Algorithm of Decision and Iterative Statements
Problem 4: Write algorithm to check if a number is Perfect number or not. A perfect number is one where Sum of
the factors excluding itself is equal to the number.
Step 1: Start.
Step 2: Accept number in n
Step 3: Initialize i to 1 and Sum to 0
Step 4: Repeat Step 5 to Step 6 while i<n
Step 5: If n%i=0 add i to Sum
Step 6: Increase i by 1
Step 7: If Sum=n then print “Perfect” else “not”
Step 8: Stop.
106106 Touchpad Computer Science-XII

