Prime number

4 way / 4 type

 

Simple way

#include<stdio.h>

int main()

{

    int n,i,count=0;

    printf("enter number=");

    scanf("%d",&n);

    for(i=2;i<n;i++)

    {

        if(n%i==0)

        {

            count++;

            break;

        }

    }

    if (count!=0)

        printf("not");

    else

        printf("%d is a prime number",n);

}

 

Perfect way

#include<stdio.h>

int main(){

    int num,i,count=0,f;

    printf("Enter a number: ");

    scanf("%d",&num);

    for(i=2;i<=num/2;i++)

    {

        if(num%i==0)

         count++;

    }

   if(count==0 && num!= 1)

        printf("%d is a prime number",num);

   else

      printf("%d is not a prime number",num);

   return 0;

}

 

Minimum to maximum range

#include<stdio.h>

int main(){

    int num,i,count,min,max;

     printf("Enter min range: ");

     scanf("%d",&min);

    printf("Enter max range: ");

    scanf("%d",&max);

    for(num = min;num<=max;num++){

         count = 0;

         for(i=2;i<=num/2;i++){

             if(num%i==0){

                 count++;

                 break;

             }

        }

         if(count==0 && num!= 1)

             printf("%d ",num);

    }

   return 0;

}

 

Maximum range

#include<stdio.h>

nt main()

   int num,i,count,n;

   printf("Enter max range: ");

   scanf("%d",&n);

   for(num = 1;num<=n;num++)

       {

        count = 0;

        for(i=2;i<=num/2;i++)

        {

            if(num%i==0)

            {

                count++;

                break;

            }

       }

        if(count==0 && num!= 1)

            printf("%d ",num);

   }

  return 0;