# Thread: scanf and printf problem?

1. ## scanf and printf problem?

Hello all, I am a complete newbie to this programming thing and am taking a intro class at school as required in my curriculum. I am having a problem where my input values are returning values of 0.000000 using a double variable in my code. Here is my code, any help would be much appreciated:
Code:
```#include <stdio.h>
#include <math.h>

int main(void)

{
double Vt,gravity,cOfDrag,mass,time;

printf("This program will use a formula to calculate the velocity\n");
printf("of a skydiver with a given formula.\n");
printf("Please enter the mass of the diver in kg in the space provided below.\n");
scanf("%lf", &mass);
printf("Please enter the coefficient of drag in kg/s in the space provided below.\n");
scanf("%lf", &cOfDrag);
printf("Please enter the time of the flight in seconds in the space provided below.\n");
scanf("%lf", &time);

gravity=9.8;

Vt=((gravity*mass)/(cOfDrag))*(1-exp(-((cOfDrag/mass))*time));

printf("%lfkg is the value entered for mass.\n", &mass);
printf("%lfkg/s is the value entered for coefficient of drag.\n", &cOfDrag);
printf("%lfs is the value entered for time of flight.\n", &time);
printf("%lfm/s is the velocity.\n", &Vt);
system("pause");

return 0;

}```

2. In your printf() you are using an ampersand on the variables, that is telling printf to print the address of this variable, which is an integral type (%d). You need to delete the ampersands to print the actual value.

Also printf()/scanf(), while valid in C++ programs they should be replaced by the C++ streams cin and cout.

Jim