Question

** Pascal ** Write a simple program in Pascal with these specifications:

1. Calculates real root of number entered by user (if root happens to be a complex number, print message "The root is complex").

2. The program keeps asking for input, user can input a key to terminate program. (e.g: Press 1 to enter calculator, Press any other key to exit calculator).

Answer 1

Program with comments to explain each step:

Program RealRootCalculator; {Name of Program}
var choice: integer; {declaring an integer type variable to store choice to enter and exit the program}
var number: real; {root of this variable will be calculated}
begin
writeln('Press 1 to enter into the real root calculator');
read(choice);
writeln('Choice = ', choice);
if choice =1 then {if user enters 1, program will enable user to calculate real roots else exit}
begin
writeln('Welcome to real root calculator');
repeat {program keep on calculating roots untill choice is 1}
writeln('Enter the number : ');
read(number);
if number < 1 then writeln('Imaginary roots') {when -ve number is entered, program will print imaginary roots}
else writeln('Root of', number:0:2,' :', sqrt(number):0:2);

writeln('Enter 1 to continue or any other key to exit');
read(choice);
until choice <> 1 {loop will be terminated when this condition, choice not equal to 1 becomes true, if user keep entering 1 then program keeps running and will not exit}
end;
writeln('exited from calculator');
end.

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Output

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Press 1 to enter into the real root calculator : 1
Welcome to real root calculator
Enter the number : 3
Root of 3.00 :1.73
Enter 1 to continue or any other key to exit : 1
Enter the number : 
Root of 5.00 :2.24
Enter 1 to continue or any other key to exit : 1
Enter the number : -5
Imaginary roots
Enter 1 to continue or any other key to exit : 5
exited from calculator