I cannot properly call the functions

[oakiboaki]

Hello. I tried to make a sort of a menu that accesses different smaller programs by calling functions (each menu option accesses a function). The problem is that when I use the calculator, my program exits after the first user input, and the poll generator skips the first user input. I cannot understand what's wrong. Please help!

Thank you!

  // 29. Test 4 - Menu With Functions.cpp

#include <iostream>
#include <string>

using namespace std;

void beer_song()
{
	int bottles = 99;
	for (;;) // The loop is used to repeat the lyrics of the song.
	{
		if (bottles > 2)
		{
			cout << bottles << " bottles of beer on the wall, " << bottles << " bottles of beer." << endl;
			cout << "Take one down and pass it around, " << --bottles << " bottles of beer on the wall." << endl << endl;
		}
		else if (bottles == 2)
		{
			cout << bottles << " bottles of beer on the wall, " << bottles << " bottles of beer." << endl;
			cout << "Take one down and pass it around, " << --bottles << " bottle of beer on the wall." << endl << endl;
		}
		else if (bottles == 1)
		{
			cout << bottles << " bottle of beer on the wall, " << bottles << " bottle of beer." << endl;
			cout << "Take one down and pass it around, no more bottles of beer on the wall." << endl << endl;
			bottles--;
		}
		else if (bottles == 0)
		{
			cout << "No more bottles of beer on the wall, no more bottles of beer." << endl;
			cout << "Go to the store and buy some more, 99 bottles of beer on the wall." << endl << endl;
			break;
		}
	}
}

void calculator()
{
	string operation;
	double x, y;
	cout << "Enter one of the four arithmetic operations (+, -, *, /): ";
	getline(cin, operation, '\n');
	cout << "Enter the first argument: ";
	cin >> x;
	cout << "Enter the second argument: ";
	cin >> y;

	if (operation == "+")
	{
		cout << "\n\nYour operation is: " << x << " " << operation << " " << y << " = ";
		cout << x + y << endl;
	}
	else if (operation == "*" || operation == "x")
	{
		cout << "\n\nYour operation is: " << x << " " << operation << " " << y << " = ";
		cout << x * y << endl;
	}
	else if (operation == "/" || operation == ":")
	{
		cout << "\n\nYour operation is: " << x << " " << operation << " " << y << " = ";
		cout << x / y << endl;
	}
	else if (operation == "-")
	{
		cout << "\n\nYour operation is: " << x << " " << operation << " " << y << " = ";
		cout << x - y << endl;
	}
	else
	{
		cout << "The type of operation you entered is not valid!" << endl;
	}
}

void poll_generator()
{
	string question, answer1, answer2, answer3;
	int answer, counter, one, two, three, i, max, egal;
	max = 0;
	counter = 1;
	one = 0;
	two = 0;
	three = 0;

	cout << "Please enter your question or the poll header:" << endl << endl;
	getline(cin, question, '\n');
	cout << "Enter the first possible answer: ";
	getline(cin, answer1, '\n');
	cout << "Enter the second possible answer: ";
	getline(cin, answer2, '\n');
	cout << "Enter the third possible answer: ";
	getline(cin, answer3, '\n');
	cout << "The poll will now start..." << endl << endl;

	cout << "The question is: " << question << endl << endl;
	cout << "The answers are:" << endl << endl;
	cout << "1." << answer1 << endl << "2." << answer2 << endl << "3." << answer3 << endl << endl;
	cout << "Answer the question by typing 1, 2 or 3, depending on your opinion. The answer ""0"" will close the poll." << endl << endl;

	for (;;)
	{
		cout << "Voter " << counter << ": ";
		cin >> answer;
		counter++;

		if (answer == 1)
		{
			one++;
		}
		else if (answer == 2)
		{
			two++;
		}
		else if (answer == 3)
		{
			three++;
		}
		else if (answer == 0)
		{
			cout << "\n\nThank you! The poll is over and the results are shown below:" << endl << endl;
			break;
		}
		else
		{
			cout << "This answer is invalid and it won't be counted in the poll!" << endl;
		}
	}

	cout << "1: ";
	for (i = 0; i <= one; i++)
	{
		cout << "| ";
	}
	cout << endl;

	cout << "2: ";
	for (i = 0; i <= two; i++)
	{
		cout << "| ";
	}
	cout << endl;

	cout << "3: ";
	for (i = 0; i <= three; i++)
	{
		cout << "| ";
	}
	cout << endl << endl;

	max = one;
	if (two > max)
	{
		max = two;
	}
	if (three > max)
	{
		max = three;
	}
	if (one == max && two != one && three != one)
	{
		cout << "It looks like the majority of votes are for " << answer1 << "." << endl;
	}
	else if (two == max && one != two && three != two)
	{
		cout << "It looks like the majority of votes are for " << answer2 << "." << endl;
	}
	else if (three == max && one != three && two != three)
	{
		cout << "It looks like the majority of votes are for " << answer3 << "." << endl;
	}
	else if (one == two && (one == max || two == max) && three != one)
	{
		cout << "It looks like is a tie match between " << answer1 << " and " << answer2 << ". Interesting situation..." << endl;
	}
	else if (one == three && (one == max || three == max) && two != one)
	{
		cout << "It looks like is a tie match between " << answer1 << " and " << answer3 << ". Interesting situation..." << endl;
	}
	else if (two == three && (two == max || three == max) && one != two)
	{
		cout << "It looks like is a tie match between " << answer2 << " and " << answer3 << ". Interesting situation..." << endl;
	}
	else if (one == two && one == three)
	{
		cout << "It looks like is a tie match between all of the answers. Is that even possible??" << endl;
	}
}

int main()
{
	cout << "Welcome to our first menu!" << endl << endl;
	for (;;)
	{
		int option;
		cout << "Please select one of the options below by typing the corresponding number: " << endl << endl;
		cout << "1. \"99 Bottles of Beer\" song" << endl;
		cout << "2. Calculator" << endl;
		cout << "3. Poll generator" << endl;
		cout << "0. Exit" << endl;
		cin >> option;

		if (option == 1)
		{
			beer_song();
			break;
		}
		else if (option == 2)
		{
			calculator();
			break;
		}
		else if (option == 3)
		{
			poll_generator();
			break;
		}
		else if (option == 0)
		{
			break;
		}
		else
		{
			cout << "This option does not exist. Please try again!" << endl << endl;
		}
	}

	cin.ignore();
	cin.get();
	return 0;
}

[mutexe]

I'm just guessing but: remove the breaks from main, except the one on line 219.

[oakiboaki]

It still doesn't work. The program keeps skipping the first user inputs from the calculator and poll generator.

[coder777]

You have a mix of operator>> and getline(). See Notes:

http://en.cppreference.com/w/cpp/string/basic_string/getline

When used immediately after whitespace-delimited input, e.g. after int n; std::cin >> n;, getline consumes the endline character left on the input stream by operator>>, and returns immediately. A common solution is to ignore all leftover characters on the line of input with cin.ignore(std::numeric_limits<std::streamsize>::max(), '\n'); before switching to line-oriented input.

[mutexe]

The problem is that when I use the calculator, my program exits after the first user input

The program keeps skipping the first user inputs from the calculator

So something has changed..

See here:
http://stackoverflow.com/questions/10553597/cin-and-getline-skipping-input

[oakiboaki]

Thank you guys! Your magic solved my problem!