Why removing a printf function messes up with my code? CS50 pset1 cash greedy challenge

Question

I finished the challenge and my first C code worked apparently well, returning each time the correct minimum number of coins needed for change. Then when I tried to "clean it up" a bit and remove a redundant printf, everything seems to go to wrong. I cannot get my brains around this one, I am very confused... Why does this happen?

#include <cs50.h>
#include <stdio.h>
#include <math.h>

int q = 25; //variable for quarters
int d = 10; //dimes
int n = 5;  //nickels
int p = 1;  //pennies

int x;  //variable for final result
int r;  // variable for the reminder

float amount(string prompt);

int main(void)
{
    float a = amount("Enter dollar amount with format 0.00: $");
    int cents = round(a * 100);
    printf("Your input: $ %.2f", a);
    // printf(", which amounts to %i total.\n", cents); //WHY DELETING THIS LINE MESSES UP WITH THE FLOAT AND THE RESULT?

    x = cents / q;
    r = cents % q;

    x = x + (r / d);
    r = r % d;

    x = x + (r / n);
    r = r % n;

    x = x + (r / p);
    printf("%i\n", x);
    r = r % p;
    printf("%i\n", r);
}

float amount(string prompt)
{
    float a;
    do {
        a = get_float("%s", prompt);
    }
    while (a <= 0);
    return a;
}

Answer 1

It was a little thing but I just couldn't see it... Removing that estatement without adding a line break above would bring the answer right after the input, so it looked to me as a misterious extra digit and missing solution (embarrasing I know...hah). Basically:

 $ ./cash3
Enter dollar amount with format 0.00: $1.12
7
0

...became...

Enter dollar amount with format 0.00: $1.12
Your input: $ 1.127
0

Sometimes looking to close to the trees make you miss the whole forest lol Thanks to Blauelf for his help and solution with this!