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#include <iostream>
#include <string>
#include <cmath>
#include <iomanip>
#include <math.h>
#include <limits>

using namespace std;

double f;
double c;
double k;
double result;


int main()
{
    cout << "Pick a temperature unit K for Kelvin, F for Fahrenheit, C for Celsius: ";
    cin >> result;
    cout << endl;
    if(result == 'f' || result == 'F')
    {
        cout << "This program will tell you what the degrees where you live is in Kelvin and Celsius." << endl;
        cout << endl;
        cout << "What's your temperature in Fahrenheit: ";

        while(!(cin >> f)){
            cin.clear();
            cin.ignore(numeric_limits<streamsize>::max(), '\n');
            cout << "Invalid temperature try again. ";
            cout << endl;
            cout << "What's your temperature in Fahrenheit: ";
    }
        cout << endl;

        k = c + 273.15;
        cout << "Your degrees in Kelvin is: " << setprecision(3) << k << " Kelvin" << endl;
        cout << endl;

        c = (f - 32) * 5 / 9;
        cout << "Your degrees in Celsius is: " << setprecision(2) << c << "Celsius" << endl;
        cout << endl;
    }

    if(result == 'c' || result == 'C')
    {
    cout << "This program will tell you what the degrees where you live is in Kelvin and Fahrenheit." << endl;
    cout << endl;
    cout << "What's your temperature in Celsius: ";

    while(!(cin >> c)){
        cin.clear();
        cin.ignore(numeric_limits<streamsize>::max(), '\n');
        cout << "Invalid temperature try again. ";
        cout << endl;
        cout << "What's your temperature in Celsius: ";
    }
        cout << endl;

        k = c + 273.15;
        cout << "Your degrees in Kelvin is: " << setprecision(3) << k << " Kelvin" << endl;
        cout << endl;

        (f = (c × 9/5) + 32);
        cout << "Your degrees in Fahrenheit is: " << setprecision(2) << f << "Fahrenheit" << endl;
        cout << endl;

    }

    if(result == 'k' || result == 'K')
    {
    cout << "This program will tell you what the degrees where you live is in Fahrenheit and Celsius." << endl;
    cout << endl;
    cout << "What's your temperature in Kelvin: ";

    while(!(cin >> k)){
        cin.clear();
        cin.ignore(numeric_limits<streamsize>::max(), '\n');
        cout << "Invalid temperature try again. ";
        cout << endl;
        cout << "What's your temperature in Kelvin: ";
    }
        cout << endl;

        f = (k − 273.15) × 9/5 + 32;
        cout << "Your degrees in Fahrenheit is: " << setprecision(2) << f << "Fahrenheit" << endl;
        cout << endl;

        c = (f - 32) * 5 / 9;
        cout << "Your degrees in Celsius is: " << setprecision(2) << c << "Celsius" << endl;
        cout << endl;
    }



    if (f <= 65)
    {
        cout << "It must be chilling outside don't forget a coat." << endl;
    }
    if (f >= 75)
    {
        cout << "It's pretty warm out no need for a coat." << endl;
    }
    if (f > 65 && f < 75)
    {
        cout << "It's a little cold but you should need a coat hopefully" << endl;
    }
    return 0;
}