Chapter 5.1, Problem 3CE

To determine

To write: a program to check whether the given number is prime or composite.

Answer to Problem 3CE

Checks if the entered number is prime or composite.

Explanation of Solution

Concept used:Use different syntax that is used to PRINT, INPUT, FOR, IF…ELSE and does other operations while writing required BASIC program.

BASIC program to check if the given numbers are prime or composite:

10 CLC

20 INT $=n,i$ ;

30 PRINT “Enter a positive integer $n$ :”

40 SET F=0;

50 FOR $i=0;i\le n/2;++i$

60 IF $n$ % $i$ ==0

70 F=1;

80 BREAK;

90 ELSE

100 IF F==1

110 PRINT “ $n$ is a Prime number.”

120 ELSE

130 PRINT “ $n$ is a composite number.”

140 RETURN 0;

150 END

Here line 30 prints message. Line 40 sets $F$ as zero to make sure that the flag is empty. Lines 50-130 checks if the number entered is prime or composite. Line 150 returns 0.

Enter an integer: $3$

  $3$ is a Prime number.

Enter an integer: $6$

  $6$ is a composite number.

Conclusion: Programs checks if the entered number is prime or composite.