Merkkijono

/*
#include <iostream>
#include <string>

using namespace std;

int main()
{
	for (int i = 0; i < 10; i++)
	{
		string curRow = "";

		for (int o = 0; o < 10; o++)
		{
			int n = i + o;
			if (n > 9)
			{
				n -= 10;
			}
			curRow += to_string(n);

			n = o - i;
			if (n < 0)
			{
				n += 10;
			}

			if (n == 0)
			{
				curRow += "A ";
			}
			else if (n == 1)
			{
				curRow += "B ";
			}
			else if (n == 2)
			{
				curRow += "C ";
			}
			else if (n == 3)
			{
				curRow += "D ";
			}
			else if (n == 4)
			{
				curRow += "E ";
			}
			else if (n == 5)
			{
				curRow += "F ";
			}
			else if (n == 6)
			{
				curRow += "G ";
			}
			else if (n == 7)
			{
				curRow += "H ";
			}
			else if (n == 8)
			{
				curRow += "I ";
			}
			else if (n == 9)
			{
				curRow += "J ";
			}
		}

		cout << curRow << "\n";
	}

	int a;
	cin >> a;

	return 0;
}*/
//Tehtävä 5

#include <iostream>
#include <string>

using namespace std;

int main()
{
	string input = "";
	cin >> input;

	bool modifyDone = false, modified = false, deleteNext = false;
	string output = "";
	char lastChar = ' ';
	while (!modifyDone)
	{
		lastChar = ' ';
		output = "";
		deleteNext = false;
		modified = false;
		for (unsigned int i = 0; i < input.length(); i++)
		{
			if (i != 0)
			{
				if (input[i] == lastChar && (!modified || deleteNext))
				{
					if (!deleteNext)
					{
						output.pop_back();
						deleteNext = true;
						modified = true;
					}
				}
				else
				{
					deleteNext = false;
					output += input[i];
					lastChar = input[i];
				}
			}
			else
			{
				lastChar = input[i];
				output += input[i];
			}
		}
		if (!modified || output.length() <= 0)
		{
			modifyDone = true;
		}
		else
		{
			input = output;
		}
	}
	cout << output << "\n";

	int a;
	cin >> a;

	return 0;
}
//Tehtävä 1

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: ACCEPTED

Test 5

Verdict: ACCEPTED

Test 6

Verdict: ACCEPTED

Test 7

Verdict: ACCEPTED

Test 8

Verdict: ACCEPTED

Test 9

Verdict: ACCEPTED

Test 10

Verdict: ACCEPTED