Can you tell me what is wrong with this code? I'm trying to convert from fahrenheit to celsius reading from format input: first temp in fahrenheit, last temp in farenheit, increment value. Stop when the first temp is larger than the last temp.

#include

#include

#include

using namespace std;

void input(double firstFah, double lastFah, double incrementValue);

double convert(double firstFah, double lastFah, double celsius, double incermentValue);

void output(double firstFah, double celsius);

int main()

{

int first=0;

int last=0;

int incre=0;

int celsius=0;

input(first, last, incre);

cin >> first >> last >> incre;

convert(first, last, celsius, incre);

output(first, celsius);

cout << first << " " << celsius;

return 0;

}//end main

void input(double, double, double) {

double firstFah=0;

double lastFah=0;

double incrementValue=0;

cout << "Enter three values as following: first temperature in fahrenheit, last temperature in fahrenheit," <<

"increment value" << endl;

cin >> firstFah >> lastFah >> incrementValue;

if (firstFah > lastFah)

cout << "Invalid value, please re-enter" << endl;

cin >> firstFah >> lastFah >> incrementValue;

}//end input

double convert(double, double, double, double) {

double firstFah = 0;

double lastFah=0;

double celsius=0;

double incrementValue=0;

while (firstFah <= lastFah) {

celsius = (firstFah - 32) * 5 / 9;

//cout << fixed << setprecision(5) << firstFah << " " << celsius << endl;

firstFah = firstFah + incrementValue;

}

return firstFah;

}//end convert

void output(double, double) {

double firstFah=0, celsius=0;

cout << fixed << setprecision(5) << firstFah << " " << celsius << endl;

}