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#include<iostream>
#include<windows.h>
using namespace std;
void math()

int main(void)
{

double mil 0.0 ;
double gal = 0.0;
double mpg = 0.0;

cout << "Enter gallons used: " << endl;
    cin >> gal;
    system("cls");

    cout << "Now enter miles driven: " << endl;
    cin >> mil;
    system("cls");

while ( gal = 0.0 )
    do{

    cout << "You can't drive a car without wasting any gas!\nStart over!" << endl;
    system("pause");
    main();

    }

while (mil = 0.0 )
    do{

    cout << "How do you manage to waste gas without driving?" << endl;
    system("pause");
    main()

    }

math();

}

void math(void)
{

mil / gal = mpg;
cout << "You entered << gal <<" as the number of gallons used. And "<< mil <<" as the number of miles traveled\nYour total Miles per gallon is: "<< mpg << "."


}

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