C program to find the first twenty prime number

/*to find the first twenty prime number*/

#include<stdio.h>

#include<math.h>

void

main()

{

                int n,i,remainder,d,c=0;

                n=1;

l1:n++;

   d=sqrt(n);

   for(i=2;i<=d;i++)

   {

                   remainder=n%i;

                   if(remainder==0)

                   {

                                   goto label;

                   }

   }

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

   c++;

label:

   if(c<=20)

                   goto l1;

}

Result:

the number 2 is prime

the number 3 is prime

the number 5 is prime

the number 7 is prime

the number 11 is prime

the number 13 is prime

the number 17 is prime

the number 19 is prime

the number 23 is prime

the number 29 is prime

the number 31 is prime

the number 37 is prime

the number 41 is prime

the number 43 is prime

the number 47 is prime

the number 53 is prime

the number 59 is prime

the number 61 is prime

the number 67 is prime

the number 71 is prime

the number 73 is prime

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