C :: Currency Conversion Control Module

Code:
/*Currency Conv Control Module*/
#include <stdio.h>
#include "currencyconv.h" /* defines constants, declares functions */
int main(void) {

float us_dollars;
float currency;
int user_input;

[Code] ....

This is $$ converter program I created that is split up over 3 files. It takes the users input in US Dollars and converts it to the currency selected. When executing the program I am encountering a small problem. It actually isn't converting anything and returns 0.00 dollars.

I would like for it to convert the amount entered into the currency selected. I would also like to add in the print statement the type of currency the user has selected.