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STL queue class

Aden8 (4)
This program reads an even number of characters. The program then prints the first character, third character, fifth character, and so on. On a second output line, the program prints the second character, fourth character, sixth character, and so on. I must use two queues to store the characters.

The program runs fine, but as soon as it's ready to display the result, I come across an error window that reads: Debug Assertion failed! with the options [Abort] [Retry] [Ignore]

I hit ignore and it displays the expected result correctly.

I believe the problems are in the FOR loops, reading an empty array element. How can I fix this? Other than that, this program is "almost" as good as done. 

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#include <iostream>
#include <stack>
#include <string>
#include <queue>
using namespace std;

int main()

{
	queue <string> input;
	queue <string> even;	
	queue <string> odd;			
	string item , newItem;
	int more;
	string item_size;
	char junk;

	 do {
			
				int i = 0;
                cout << "Enter a sentence ('.' to stop): ";
                cin >> item;
                while (cin && item != ".")
				{
					if (item.length()%2==1)
						input.push(item);
					else
						input.push(item);
                     cin >> item;
				}


				while(!input.empty())
				{
					item = input.front();
					item_size = item;
					input.pop();

					if(item[0] != NULL)
					{

						for(int j = 1; j < item_size.length(); j++)
						{
							if (j % 2 == 0)
							{
								j++;
							}

							newItem = item[j];
							odd.push(newItem);
						}


					for(int j = 0; j < item_size.length(); j++)
						{
							if (j % 2 != 0)
							{
								j++;
							}

							newItem = item[j];
							even.push(newItem);
						}
						
					}

				}


			while (!even.empty())
				{
                    cout << even.front() << " ";   // print the top character
                    even.pop();          // remove top character
                }

			cout << endl;

	       while (!odd.empty())
				{
                        cout << " " << odd.front();   // print the top character
                        odd.pop();          // remove top character
                }


	            cout << endl;

                cout << "More (0/1)?";
                cin >> more;
                cin.get(junk);

	 } while(more == 1);

	cout << endl;
	system("pause");
	return 0;

}







Enter a sentence ('.' to stop): happy
.

//ERROR WINDOW APPEARS HERE WITH THREE OPTIONS, CLICK [IGNORE].

h p y
 a p
More (0/1)?
Last edited on
vlad from moscow (6539)
Why did you declare these variables

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	queue <string> input;
	queue <string> even;	
	queue <string> odd;			
	string item , newItem;
	int more;
	string item_size;
	char junk;


outside the do-while loop if they all except 'more' and 'queue(s)' are used only inside the loop?!

And I do not understand such a silly code as

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if (item.length()%2==1)
	input.push(item);
else
	input.push(item);


What does it mean?
Last edited on
coder777 (8439)
this is one of the most over complicated programs I've seen so far...

the assertion will arise on line 51 and 63. reason: due to the preceding j++; the last access to item[j]; is out of bounds
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