check_end_of_sentence

// By Earl Walker - 1212156

#include <iostream>
#include <vector>
#include <string>
#include <locale>

using namespace std;

//#define MANUALLY_INPUT 


// Take the characters between @from and @to from the passage string to form a word.
string to_word(string passage, int from, int to)
{
	string word;

	for (int i = from + 1; i != to; i++)
	{
		if (passage[i] == ' ')
			return "";
		word.push_back(passage[i]);
	}
	return word;
}

// As the above but form a sentence. Insert '.' at the end.
string to_sentence(vector<string> passage, int from, int to)
{
	string sentence;
	for (int i = from + 1; i != to; i++)
	{
		sentence.append(passage[i]);
		if (i != to - 1)
			sentence.append(" ");
		else
			sentence.append(".");
	}
	return sentence;
}

bool is_number(const std::string& s)
{
	string::const_iterator iter = s.begin();
	while (iter != s.end() && isdigit(*iter))
		iter++;
	return !s.empty() && iter == s.end();
}

void main()
{
	string passage;
#ifdef MANUALLY_INPUT
	cout << "Input passage: ";
	getline(cin, passage);
#else
	passage = "   Parts 1 and 3 can be easily done with pillow, \
but part 2 can be a little tricky(like 20 mins of experimentation). \
Fortunately, this is Python and someone on the internet has already spent those 20 minutes. \
Mr. Watson says 0.2, 0.3, 1.2, etc. are not the end of this sentence. \
We use this image_utils module that does exactly what we need. \
To make it work for pillow(it is written for PIL), take a look at porting pil code to pillow. \
It is just a matter of changing the imports. The example code in the link is quite self explanatory.";
#endif

	vector<string> objects;
	int last_index = -1;

	for (size_t size = passage.length(), i = 1; i != size; i++)
	{
		if (passage[i] == ' ' || passage[i] == '.' || passage[i] == '?' || passage[i] == '!' || passage[i] == '\n')
		{
			string word = to_word(passage, last_index, i);
			if (word != "")
				objects.push_back(word);
			if (passage[i] != ' ')
				objects.push_back(".");
			last_index = i;
		}
	}

	vector<string> IGNORE_PREFIX_LIST = {"mr", "mrs", "dr"};
	vector<string> IGNORE_SUFFIX_LIST = { "txt", "exe", "rar", "zip", "mp3", "mp4" };
	vector<string> sentences;
	last_index = -1;
	bool is_end_of_sentence;

	for (size_t size = objects.size(), i = 0; i != size; i++)
	{
		//cout << objects[i] << '\n';
		if (objects[i] == ".")
		{
			int prev = i - 1;
			is_end_of_sentence = true;
			if (prev >= 0)
			{
				for (int d = 0; d != IGNORE_PREFIX_LIST.size(); d++)
				{
					if (_strcmpi(objects[prev].c_str(), IGNORE_PREFIX_LIST[d].c_str()) == 0)
					{
						is_end_of_sentence = false;
						break;
					}
				}

				if (is_end_of_sentence)
				{
					int next = i + 1;
					if (next < size)
					{
						for (int d = 0; d != IGNORE_SUFFIX_LIST.size(); d++)
						{
							if (_strcmpi(objects[next].c_str(), IGNORE_SUFFIX_LIST[d].c_str()) == 0)
							{
								is_end_of_sentence = false;
								break;
							}
						}
						if (is_number(objects[prev]) && is_number(objects[next]))
						{
							is_end_of_sentence = false;
						}
						else if (objects[prev] == "etc" && islower(objects[next][0]))
						{
							is_end_of_sentence = false;
						}
					}
				}
			}
			if (is_end_of_sentence)
			{
				sentences.push_back(to_sentence(objects, last_index, i));
				last_index = i;
			}
		}
	}

	for (size_t size = sentences.size(), i = 0; i != size; i++)
	{
		cout << sentences[i] << '\n';
	}
}