Question

write a program to input an integer and check whether it is a prime number or not

Answer 1

#include <stdio.h> int main() { int n, i, flag = 0; printf("Enter a positive integer: "); scanf("%d", &n); for(i = 2; i <= n/2; ++i) { // condition for nonprime number if(n%i == 0) { flag = 1; break; } } if (n == 1) { printf("1 is neither a prime nor a composite number."); } else { if (flag == 0) printf("%d is a prime number.", n); else printf("%d is not a prime number.", n); } return 0; }


Output

Enter a positive integer: 29 29 is a prime number.

Answer 2

CODE

import java.util.*;

class prime

{

public void main()

{

Scanner sc=new Scanner(System.in);

System.out.println("Enter a number to check whether it is prime or not");

int n=sc.nextInt();

int c=0;

for(int i=1;i<=n;i++)

{

if(n%i==0)

{

c++;

}

}

if(c==2)

{

System.out.println("Prime number");

}

else

{

System.out.println("Not a prime numer");

}

}

}

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Hope it helps :-)

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