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MENU DRIVEN LOOP

JKirn05 (5)
Ok guys, this program runs and compiles. As long as you don't try to go backwards on the menu. I have been searching for 2 hours trying to figure out how to fix it.
Post the menu
get user input
do what 1 is supposed to do
repost menu and ask for input again
do what it says.... so on and so forth.
My problem is that when it asks for menu, it doesnt go back to start of program to validate from the start, it picks up right there and only goes down the code.
Please help...
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// vending.cpp
// Name: Jeff Kirn
// Date: 9/11/14
// This program will act as a vending machine

#include <iostream>
#include <iomanip>
#include <cstring>
#include <string>
#include <fstream>
#include <cstdlib>
using namespace std;
struct Candy
{
	
	double price;
	string name = "";
	int count;
};




void menu();
	
int main()
{
	double totalSales = 0;
	if (totalSales >0)
	{
		cout<<"So far your cost of candy is $"<<totalSales<<endl;
	}
	cout<<"Please press \n1:Snickers\t$1.00\n2:M&Ms\t\t$1.00\n3:Cheetos\t$1.50\n4:Exit"<<"\n"<<endl;
	Candy vend[3];
	int input = 0;
	double total = 0;
	double quant = 0;
	double dollars = 0;
	double tranPrice = 0;
	double sPrice = 1.00,
			mPrice = 1.00,
			cPrice = 1.50;
	double bills =0;
	double change = 0;
//	double totalSales = 0;
	
	vend[0].price = 1.00;
	vend[0].name = "Snickers";
	vend[0].count = 5;
	
//	cout<<vend[0].name<<endl;
//	cout<<vend[0].price<<"\t"<<endl;
//	cout<<vend[0].count<<"\t"<<endl;
	vend[1].name = "M&Ms";
	vend[1].price= 1.00;
	vend[1].count = 5;
	
	vend[2].name = "Cheetos";
	vend[2].price = 1.50;
	vend[2].count = 5;
	
	cin>>input;
//	menu(input);

	
	if (input == 1)
	{
		cout<<"You have chosen "<<vend[input-1].name<<endl;
		if( vend[input-1].count <= 0)
		{
			cout<<"Sold out"<<endl;
		}
		if( vend[input-1].count>=1)
		{
		
		cout<<"There are "<<vend[input-1].count<<" "<<vend[input-1].name<<" in the machine"<<endl;
		cout<<"How many would you like to buy? : ";
		cin>>quant;
		tranPrice = quant * sPrice;
	//	tranprice =  quant *vend[intput-1].price;
		cout<<"The price of "<<quant<<" "<< vend[input-1].name<<" is $"<<tranPrice<<endl;
		cout<<"How much money will you be putting in? : ";
		cin>>bills;
		change = bills - tranPrice;
		if (change<0)
		{
			cout<<"Not enough money"<<endl;
			cout<<"The price of "<<quant<<" "<< vend[input-1].name<<" is $"<<tranPrice<<endl;
			cout<<"How much money will you be putting in? : ";
			cin>>bills;
					{
			cout<<"Here is your snack"<<endl;
			totalSales = totalSales + tranPrice;
						vend[input-1].count -=  quant;
			cout<<vend[input-1].count<<endl;
		}
		}
		if(change>=0)
		{
			cout<<"Here is your snack"<<endl;
			totalSales = totalSales + tranPrice;
			vend[input-1].count -=  quant;
			cout<<vend[input-1].count;
		}
		}
		menu();
		//	cout<<"Please press \n1:Snickers\t$1.00\n2:M&Ms\t\t$1.00\n3:Cheetos\t$1.50\n4:Exit"<<"\n"<<endl;
			cin>>input;
		//	menu(input);
		//main();
	}
	
		if (input == 2)
	{
		cout<<"You have chosen "<<vend[input-1].name<<endl;
		if( vend[input-1].count <= 0)
		{
			cout<<"Sold out"<<endl;
		}
		if( vend[input-1].count>=1)
		{
		
		cout<<"There are "<<vend[input-1].count<<" "<<vend[input-1].name<<" in the machine"<<endl;
		cout<<"How many would you like to buy? : ";
		cin>>quant;
		tranPrice = quant * sPrice;
	//	tranprice =  quant *vend[intput-1].price;
		cout<<"The price of "<<quant<<" "<< vend[input-1].name<<" is $"<<tranPrice<<endl;
		cout<<"How much money will you be putting in? : ";
		cin>>bills;
		change = bills - tranPrice;
		if (change<0)
		{
			cout<<"Not enough money"<<endl;
			cout<<"The price of "<<quant<<" "<< vend[input-1].name<<" is $"<<tranPrice<<endl;
			cout<<"How much money will you be putting in? : ";
			cin>>bills;
					{
			cout<<"Here is your snack"<<endl;
			totalSales = totalSales + tranPrice;
						vend[input-1].count -=  quant;
			cout<<vend[input-1].count<<endl;
		}
		}
		if(change>=0)
		{
			cout<<"Here is your snack"<<endl;
			totalSales = totalSales + tranPrice;
			vend[input-1].count -=  quant;
			cout<<vend[input-1].count;
		}
		}
		menu();
		cin>>input;
		//	cout<<"Please press \n1:Snickers\t$1.00\n2:M&Ms\t\t$1.00\n3:Cheetos\t$1.50\n4:Exit"<<"\n"<<endl;
		//	cin>>input;
		//main();
	}
	
		if (input == 3)
	{
		cout<<"You have chosen "<<vend[input-1].name<<endl;
		if( vend[input-1].count <= 0)
		{
			cout<<"Sold out"<<endl;
		}
		if( vend[input-1].count>=1)
		{
		
		cout<<"There are "<<vend[input-1].count<<" "<<vend[input-1].name<<" in the machine"<<endl;
		cout<<"How many would you like to buy? : ";
		cin>>quant;
		tranPrice = quant * cPrice;
	//	tranprice =  quant *vend[intput-1].price;
		cout<<"The price of "<<quant<<" "<< vend[input-1].name<<" is $"<<tranPrice<<endl;
		cout<<"How much money will you be putting in? : ";
		cin>>bills;
		change = bills - tranPrice;
		if (change<0)
		{
			cout<<"Not enough money"<<endl;
			cout<<"The price of "<<quant<<" "<< vend[input-1].name<<" is $"<<tranPrice<<endl;
			cout<<"How much money will you be putting in? : ";
			cin>>bills;
					{
			cout<<"Here is your snack"<<endl;
			totalSales = totalSales + tranPrice;
			vend[input-1].count -=  quant;
			cout<<vend[input-1].count<<endl;
		}
		}
		if(change>=0)
		{
			cout<<"Here is your snack"<<endl;
			totalSales = totalSales + tranPrice;
					
			vend[input-1].count -=  quant;
			cout<<vend[input-1].count<<endl;
		}
		}
				menu();
		cin>>input;
		//	cout<<"Please press \n1:Snickers\t$1.00\n2:M&Ms\t\t$1.00\n3:Cheetos\t$1.50\n4:Exit"<<"\n"<<endl;
		//	cin>>input;
		//main();
	}
	if (input == 4)
	{
		cout<<"The machine has "<<vend[0].count<<" "<< vend[0].name<<" "<<vend[1].count<<" "<< vend[1].name<<" "<<vend[2].count<<" "<< vend[2].name<<" left inside"<<endl;
		cout<<"You spent $"<<totalSales;
	}
	

	return 0;
}
void menu()
{
		int input = 0;
		cout<<"Please press \n1:Snickers\t$1.00\n2:M&Ms\t\t$1.00\n3:Cheetos\t$1.50\n4:Exit"<<"\n"<<endl;
	//	cin>>input;
	//	return input;
}
Albatross (4553)
I don't mean to be cryptic here, but this is exactly the sort of situation where a do-while loop would be useful. It would allow you to jump all the way back up to the top of your menu code without needing to resort to recursion (I see those commented-out main() calls).
http://www.cplusplus.com/doc/tutorial/control/#dowhile

You may need to rearrange some parts of your code near the top of main to properly use it.

-Albatross
JKirn05 (5)
Sounds good, I will give it a try, THANK YOU!!
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