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2 questions, array and looping

football52 (176)
First question

The code was working just fine until I started to do some tuning to my program. I added the array string item[10] {"", "", "", "",.....}

When I run the program, as soon as I enter the 10th item name windows pops up saying "Program" has stopped working. And forces me to close it by entering another key to close it.

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  string item[10] {"", "", "", "", "", "", "", "", "", ""};
	cout << "Enter the ten items that you bought at " << store << ". The first item is: " << item[1] << endl;
	getline(cin, item[1]);
	cout << "The second item is: " << endl;
	getline(cin, item[2]);
	cout << "The third item is: " << endl;
	getline(cin, item[3]);
	cout << "The fourth item is: " << endl;
	getline(cin, item[4]);
	cout << "The fifth item is: " << endl;
	getline(cin, item[5]);
	cout << "The sixth item is: " << endl;
	getline(cin, item[6]);
	cout << "The seventh item is: " << endl;
	getline(cin, item[7]);
	cout << "The eigth item is: " << endl;
	getline(cin, item[8]);
	cout << "The ninth item is: " << endl;
	getline(cin, item[9]);
	cout << "The tenth item is: " << endl;
	getline(cin, item[10]);


Second Question

Before I implemented that array, this set of code works but to get from the price of 1 item to the next I have to enter the price twice. Example is if item #1 is $5 I have to enter 5, it skips to the next line and I enter 5 again then it will move to item #2

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double itemPrice[10] {0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
	bool price = false;
	do
	{
		cout << "What was the price of " << item[1] << "?" << endl;
		cin >> itemPrice[1];
		while (!(cin >> itemPrice[1]) || itemPrice[1] <= 0)
		{
			cout << "Invalid price, enter a new amount." << endl;
			cin.clear();

			cin.ignore(1000, '\n');
		}
	} while (itemPrice[1] <= 0);
	do
	{
		cout << "What was the price of " << item[2] << "?" << endl;
		cin >> itemPrice[2];
		while (!(cin >> itemPrice[2]) || itemPrice[2] <= 0)
		{
			cout << "Invalid price, enter a new amount." << endl;
			cin.clear();

			cin.ignore(1000, '\n');
		}
	} while (itemPrice[2] <= 0);
RadWayne (97)
arrays and vectors start at place 0. So int myArray[3] would be myArray[0], myArray[1], myArray[2].
closed account (2b5z8vqX)

First question

The code was working just fine until I started to do some tuning to my program. I added the array string item[10] {"", "", "", "",.....}

When I run the program, as soon as I enter the 10th item name windows pops up saying "Program" has stopped working. And forces me to close it by entering another key to close it.


 
 
getline(cin, item[10]);

The coerced termination of your software results from the attempted access of a non-existent array element, which is done during the execution of the preceding statement. Know that the elements within an array are accessed using the indexes [0, N); in other words, it is acceptable only to enclose an integer between zero and the size of the array minus one in square brackets.

http://en.cppreference.com/w/cpp/language/array

I have modified your source code to correct the error.

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string item[10] {"", "", "", "", "", "", "", "", "", ""};
cout << "Enter the ten items that you bought at " << store 
     << ". The first item is: " << item[1] << endl;
getline(cin, item[0]);
cout << "The second item is: " << endl;
getline(cin, item[1]);
cout << "The third item is: " << endl;
getline(cin, item[2]);
cout << "The fourth item is: " << endl;
getline(cin, item[3]);
cout << "The fifth item is: " << endl;
getline(cin, item[4]);
cout << "The sixth item is: " << endl;
getline(cin, item[5]);
cout << "The seventh item is: " << endl;
getline(cin, item[6]);
cout << "The eigth item is: " << endl;
getline(cin, item[7]);
cout << "The ninth item is: " << endl;
getline(cin, item[8]);
cout << "The tenth item is: " << endl;
getline(cin, item[9]);
football52 (176)
Ah thank you, any of kyou know about by 2nd question
AbstractionAnon (6954)
Before I implemented that array, this set of code works but to get from the price of 1 item to the next I have to enter the price twice. Example is if item #1 is $5 I have to enter 5, it skips to the next line and I enter 5 again then it will move to item #2

That's because you're inputting the price twice. 

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    cin >> itemPrice[1];
    while (!(cin >> itemPrice[1]) || itemPrice[1] <= 0)


What you probably meant was to check the status of cin, rather that inputting itemPrice a second time.
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    cin >> itemPrice[1];
    while ((! cin) || itemPrice[1] <= 0)


Last edited on
football52 (176)
Thank you it worked
football52 (176)
Actually, I tested it to see what happens if I put in an invalid price like "h" or any character, Invalid Price gets printed twice and anything I enter from there on whether it be a number or character outputs Invalid Price

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do
	{
		cout << "What was the price of " << item[0] << "?" << endl;
		cin >> itemPrice[0];
		while ((!cin) || itemPrice[0] <= 0)
		{
			cout << "Invalid price, enter a new amount." << endl;
			cin.clear();

			cin.ignore(10000, '\n');
		}
	} while (itemPrice[0] <= 0);
football52 (176)
Bump
AbstractionAnon (6954)
If cin is invalid or itemPrice is <= 0, you will never exit the loop at line 5 since you never do another input operation.
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