Why the function getchar () is skipped, and does not run in the above program in C

[timcook]

/*I tried to make a simple program, that calculate: 
 *1) how much money will cost us a product if we have percentage decrease for it; 
 *2) how much money we can save after buying a reduced/decreased product versus its real price; */


/*I want to implement some of the two cases in switch statement, but the program does not allow me to do that, because the getchar () function is skipped*/


#include <stdio.h>


int main (void)
{
    float real_price, percentage;
    char ch;


    printf ("Enter the real price of the product: ");
    scanf ("%f", &real_price);
    printf ("\nEnter the percentage decrease: ");
    scanf ("%f", &percentage);


    printf ("\nPress 1 if you want to calculate the PRICE OF THE PRODUCT AFTER THE REDUCING\nPress 2 if you want to calculate THE REDUCED PRICE OF THE PRODUCT: ");
    ch = getchar ();  //this statement is not implemented


    switch (ch) {
        case '1':
            printf ("The price of the product after the reducing is: %f ", real_price - (percentage / 100) * real_price);


        case '2':
            printf ("The reduced price of the product is: %f", (percentage/100)*real_price);
            break;


        default:
            printf ("getchar () is not implemented\n");  //respectively this statement is implemented
    }


    return 0;
}

[OldGuy2]

scanf leaves '\n' in the input buffer, that's what getchar reads so it doesn't stop for input.
To fix put another getchar after the last scanf.

[timcook]

I understand you and i am thankful for your explanation and advice, but I do not understand a few things associated about what you wrote about getchar()
First thing: why scanf() still keeps the '\n' after releasing the '\n' on printf() ?
Second thing: why scanf() does not release the '\n' on such functions as getche(), getch() ?

[GReaper]

1) Because its input is buffered, and it doesn't discard characters willy-nilly.
2) Because getche() and getch() aren't buffered

[timcook]

I understand the conception, and I will follow the URLs that you shared with me. Thank you very much!!!