1 // next immdiate prime number using do while
    2 #include <stdio.h>
    3 int main()
    4 {
    5 	int  num,i,j=1,count=0;
    6 	scanf("%d",&num);
    7 	i = num+1; //checking from next number
    8     do
    9     {
   10       do
   11       {
   12       	if(i%j==0)
   13         {
   14           count++;   //counting number of factors of a number
   15         }
   16         if(count >2)
   17         {
   18           continue;
   19         }
   20         j++;
   21       }while(j<=i);
   22       if(count ==2)
   23       {
   24         printf("%d",i);
   25         return 0;
   26       }
   27      count=0;
   28      j=1; // setting the j flag
   29      i++;
   30    }while(1);  // infinite loop until next immediate prime is found
   31
   32 	return 0;
   33 }