How to wrap integer if greater than a certain number?

[strawberryunicorn]

Program asks for current month, the rainfall and the average rainfall for each of the 12 previous months & puts them into a chart, then you can switch between chart and graph view. Everything works except in the graph, the rainfalls and average rainfalls always start with january's numbers. It's supposed to start with the current month's numbers then go in order. How do I get the numbers to start at the current month and wrap around? Like if the month is august it might go like 8 9 10 11 12 1 2..

(cut beginning part because code is too long)

int main()
{
	char input = 'Y';
	do
	{
		int currentMonth;
		double rainfall[11];
		double avg[11];
		int count2 = 0;
		int month;
		int countfunction = 0;
		input = 't';
		string monthsOfYear[12] = { "Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec" };


		//Input current month
		cout << "What is the number of the current month? Jan = 1, Feb = 2, etc." << endl;
		cin >> currentMonth;
		month = currentMonth - 1;


		//Input average rainfall for each month
		cout << "\nPlease enter average rainfall for each month" << endl;
		for (int i = currentMonth - 1; count2 < 12; i = (i + 1) % 12, count2++)
		{
			outputMonth(i);
			cout << ": ";
			cin >> avg[i];
		}


		//Input rainfall for each month
		cout << "\nPlease enter the rainfall for each month in the previous year" << endl;
		int count = 0;
		for (int month = currentMonth - 1; count < 12; month = (month + 1) % 12, count++)
		{
			outputMonth(month);
			cout << ": ";
			cin >> rainfall[month];
		}
		cout << " " << endl;
		system("pause");
		system("cls");


		tableChart(avg, rainfall, month, countfunction, monthsOfYear);
		cout << "\nEnter t to see table view or g to see graph view or enter y to restart: " << endl;
		cin >> input;
		cout << "\n";
		system("cls");

		while (input == 't' || input == 'g')
		{

			{

				if (countfunction == 12)
					countfunction = 0;
				while (input == 'g')
				{
					graph(avg, rainfall, month, countfunction);
					cout << "\nEnter t to see table view or g to see graph view or y to restart:  \n";
					cin >> input;
					system("cls");
					if (countfunction == 12)
						countfunction = 0;
				}
				while (input == 't')
				{
					tableChart(avg, rainfall, month, countfunction, monthsOfYear);
					cout << "\nEnter t to see table view or g to see graph view or y to restart: \n";
					cin >> input;
					cout << "\n" << endl;
					system("cls");
					if (countfunction == 12)
						countfunction = 0;
				}
			}

		} while (input == 't' || input == 'g');
	} while (input == 'y');
}

string printMonth(int& month, string date[], int& counter)
{
	for (int i = month; counter < 12;)
	{
		month = (month + 1) % 12;
		counter++;
		return date[i];
	}
}

void outputMonth(int month)
{
	cout.fill('_');
	cout.width(8);
	switch (month)
	{
	case 0:
		cout << left << "Jan";
		break;

	case 1:
		cout << left << "Feb";
		break;

	case 2:
		cout << left << "March";
		break;

	case 3:
		cout << left << "April";
		break;

	case 4:
		cout << left << "May";
		break;

	case 5:
		cout << left << "June";
		break;

	case 6:
		cout << left << "July";
		break;

	case 7:
		cout << left << "Aug";
		break;

	case 8:
		cout << left << "Sept";
		break;

	case 9:
		cout << left << "Oct";
		break;

	case 10:
		cout << left << "Nov";
		break;

	case 11:
		cout << left << "Dec";
		break;
	}
}
void swapValues(string& v1, string& v2)
{
	string switcharoo;
	switcharoo = v1;
	v1 = v2;
	v2 = switcharoo;

}
//Chart starts here. the values that are wrong are rainfall[1], rainfall[2], rainfall[3].. and avg[1], avg[2], avg[3]...
void tableChart(double avg[], double rainfall[], int& month, int& 
countfunction, string monthsOfYear[])

{
	int i = month;
	cout << setfill('-') << setw(1) << "+" << setw(10) << "-" << setw(1) << "+" << setw(10) << "-" << setw(1) << "+" << setw(10) << "-" << setw(1) << "+" << setw(10) << "-" << setw(1) << "+" << endl;
	cout << setfill(' ') << setw(1) << "|" << setw(10) << left << "Month" << "|" << setw(10) << left << "Rainfall" << setw(1) << "|" << setw(10) << left << "Average" << setw(1) << "|" << setw(1) << left << "Difference" << setw(1) << "|" << endl;
	cout << setfill('-') << setw(1) << "+" << setw(10) << "-" << setw(1) << "+" << setw(10) << "-" << setw(1) << "+" << setw(10) << "-" << setw(1) << "+" << setw(10) << "-" << setw(1) << "+" << endl;
	cout << setfill(' ') << setw(1) << "|" << setw(10) << left << printMonth(month, monthsOfYear, countfunction) << "|" << setw(10) << left << rainfall[i] << setw(1) << "|" << setw(10) << left << avg[0] << setw(1) << "|" << setw(10) << left << rainfall[0] - avg[0] << setw(1) << "|" << endl;
	cout << setfill(' ') << setw(1) << "|" << setw(10) << left << printMonth(month, monthsOfYear, countfunction) << "|" << setw(10) << left << rainfall[i] << setw(1) << "|" << setw(10) << left << avg[1] << setw(1) << "|" << setw(10) << left << rainfall[1] - avg[1] << setw(1) << "|" << endl;
	cout << setfill(' ') << setw(1) << "|" << setw(10) << left << printMonth(month, monthsOfYear, countfunction) << "|" << setw(10) << left << rainfall[i] << setw(1) << "|" << setw(10) << left << avg[2] << setw(1) << "|" << setw(10) << left << rainfall[2] - avg[2] << setw(1) << "|" << endl;
	cout << setfill(' ') << setw(1) << "|" << setw(10) << left << printMonth(month, monthsOfYear, countfunction) << "|" << setw(10) << left << rainfall[i] << setw(1) << "|" << setw(10) << left << avg[3] << setw(1) << "|" << setw(10) << left << rainfall[3] - avg[3] << setw(1) << "|" << endl;
	cout << setfill(' ') << setw(1) << "|" << setw(10) << left << printMonth(month, monthsOfYear, countfunction) << "|" << setw(10) << left << rainfall[i] << setw(1) << "|" << setw(10) << left << avg[4] << setw(1) << "|" << setw(10) << left << rainfall[4] - avg[4] << setw(1) << "|" << endl;
	cout << setfill(' ') << setw(1) << "|" << setw(10) << left << printMonth(month, monthsOfYear, countfunction) << "|" << setw(10) << left << rainfall[i + 5] << setw(1) << "|" << setw(10) << left << avg[5] << setw(1) << "|" << setw(10) << left << rainfall[5] - avg[5] << setw(1) << "|" << endl;
	cout << setfill(' ') << setw(1) << "|" << setw(10) << left << printMonth(month, monthsOfYear, countfunction) << "|" << setw(10) << left << rainfall[i + 6] << setw(1) << "|" << setw(10) << left << avg[6] << setw(1) << "|" << setw(10) << left << rainfall[6] - avg[6] << setw(1) << "|" << endl;
	cout << setfill(' ') << setw(1) << "|" << setw(10) << left << printMonth(month, monthsOfYear, countfunction) << "|" << setw(10) << left << rainfall[i + 7] << setw(1) << "|" << setw(10) << left << avg[7] << setw(1) << "|" << setw(10) << left << rainfall[7] - avg[7] << setw(1) << "|" << endl;
	cout << setfill(' ') << setw(1) << "|" << setw(10) << left << printMonth(month, monthsOfYear, countfunction) << "|" << setw(10) << left << rainfall[i + 8] << setw(1) << "|" << setw(10) << left << avg[8] << setw(1) << "|" << setw(10) << left << rainfall[8] - avg[8] << setw(1) << "|" << endl;
	cout << setfill(' ') << setw(1) << "|" << setw(10) << left << printMonth(month, monthsOfYear, countfunction) << "|" << setw(10) << left << rainfall[i + 9] << setw(1) << "|" << setw(10) << left << avg[9] << setw(1) << "|" << setw(10) << left << rainfall[9] - avg[9] << setw(1) << "|" << endl;
	cout << setfill(' ') << setw(1) << "|" << setw(10) << left << printMonth(month, monthsOfYear, countfunction) << "|" << setw(10) << left << rainfall[i + 10] << setw(1) << "|" << setw(10) << left << avg[10] << setw(1) << "|" << setw(10) << left << rainfall[10] - avg[10] << setw(1) << "|" << endl;
	cout << setfill(' ') << setw(1) << "|" << setw(10) << left << printMonth(month, monthsOfYear, countfunction) << "|" << setw(10) << left << rainfall[i + 11] << setw(1) << "|" << setw(10) << left << avg[11] << setw(1) << "|" << setw(10) << left << rainfall[11] - avg[11] << setw(1) << "|" << endl;
	cout << setfill('-') << setw(1) << "+" << setw(10) << "-" << setw(1) << "+" << setw(10) << "-" << setw(1) << "+" << setw(10) << "-" << setw(1) << "+" << setw(10) << "-" << setw(1) << "-" << endl;
	return;
}

void graph(double avg[], double rainfall[], int& month, int& countfunction)
{
	int counter2 = 0;
	for (int i = month; counter2 < 12;)
	{
		outputMonth(month);
		cout << " " << endl;
		cout << "Rainfall: ";
		printAsterisks(rainfall[i]);
		cout << "Average: ";
		printAsterisks(avg[i]);
		i = (i + 1) % 12;
		counter2++;
		cout << " " << endl;
		month = (month + 1) % 12;
	}
}

void printAsterisks(double n)
{
	for (int count = 0; count < n; count++)
	{
		cout << "*";
	}
	cout << endl;
}

[48T7M4Gy]

Use modular arithmetic. eg If starting month is 8 August and you go 20 months then the 28th month is 28 % 12 which is 4 i.e. April

[dhayden]

int currentMonth = 7;
for (int i = 0; i<12; ++i) {
    int month = (currentMonth+i) % 12;
    cout << month << '\n';
}

[strawberryunicorn]

kemort I can't get it to work without the last month values come out as hexidecimal.
dhayden how do I make it so it takes the currentMonth that the user inputs? like not just 7 but whatever month number they entered.

never mind. I spent hours trying to understand this and I have a headache so I give up. -_-

[dhayden]

I was just setting currentMonth=7 as an example. Simply delete that line and use whatever value of currentMonth the user input.

[48T7M4Gy]

Keep in mind first month is monthsOfYear[0]

Note: hexadecimal isn't relevant here

#include <iostream>
#include <string>

int main()
{
  std::string monthsOfYear[] = { "Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec" };
  
  int month = 0;
  
  for (int i = 0; i < 24; i++)
  {
     std::cout << i << '\t' << monthsOfYear[i % 12] << std::endl;
  }
  
  std::cout << "Enter a month number: ";
  std::cin >> month;
  std::cout << " = " << monthsOfYear[ month % 12 ] << std::endl;
}

[dhayden]

I was setting currentMonth=7 as an example. Just delete that line and use whatever value of currentMonth the user input.