main()                                                      
   {                                                  
       float x,y;                                              
       double p,q;                                             
       printf("Values of x and y:");                           
       scanf("%f %e", &x, &y);                                 
       printf("\n");                                           
       printf("x = %f\ny = %f\n\n", x, y);                     
       printf("Values of p and q:");                           
       scanf("%lf %lf", &p, &q);                               
       printf("\np = %lf\nq = %e",p,q);                        
       printf("\n\np = %.12lf\np = %.12e", p,q);               
   }                                                           

Output                                                      
                                                               
   Values of x and y:12.3456  17.5e-2                          
   x = 12.345600                                               
   y = 0.175000                                                
   Values of p and q:4.142857142857  18.5678901234567890       
   p = 4.142857142857                                          
   q = 1.856789012346e+001