1-100 prime numbers

            main()  
            {  
                int r, c, k;  
                clrscr();  
            
                for(r = 1; r <= 100; r++)  
                {  
                    k = 0;  
                    for(c = 2; c <= r - 1; c++)  
                    {  
                        if(r % c == 0)  
                        {  
                            k = 1;  
                        }  
                    }  
                    if(k == 0)  
                    {  
                        printf("\n %d", r);  
                    }  
                }  
                getch();  
            }  
            

Output: