#include <stdio.h>
/* This program takes two inputs acceleration
    and mass, and ouputs the force = mass*acceleration */

void force(double m, double accel);

int main() {
    /* Added accel */
    double mass, accel;
    /* Changed %d to %lf since it is declared with double */
    printf("Enter an acceleration: ");
    scanf("%lf", &accel);
    /* Changed %d again to %lf for the same reason as above */
    printf("Enter the mass of the object: ");
    scanf("%lf", &mass);

    force(mass, accel);

    printf("You entered %lf m/s^2\n", accel);
    printf("You entered %lf kg\n", mass);

    return 0;
}

/* Declared mass too */
void force(double m, double accel, double mass) {
    mass = m / 1000;

    printf("The force is %lf milliNewtons\n", mass * accel);

    accel = accel*1000;

    printf("The force is %lf Newtons\n\n", mass * accel);
}