lab04-bits/bits 4/bits 4.cpp

#include <iostream>
#include <fstream>
#include <string>

using namespace std;

int main() {
	char fileName[260];
	cin.getline(fileName, 260);

	if (strchr(fileName, '*') || strchr(fileName, '"') || strchr(fileName, '<') ||
		strchr(fileName, '>') || strchr(fileName, '?') || strchr(fileName, '|') ||
		strchr(fileName + 2, ':') || (fileName[0] == ':')) {
		cout << "Invalid path" << endl;
		return 1;
	}

	if (fileName[1] == ':' && (!isalpha(fileName[0]) || fileName[2] != '\\')) {
		cout << "Invalid path" << endl;
		return 1;
	}

	if (strrchr(fileName, '.') && (strrchr(fileName, '.') > strrchr(fileName, '\\')) && (strrchr(fileName, '.') > strrchr(fileName, '/'))) {
		char* ext = strrchr(fileName, '.') + 1;

		if (strlen(ext) != 3) {
			cout << "Invalid path" << endl;
			return 1;
		}

		ext[0] = tolower(ext[0]);
		ext[1] = tolower(ext[1]);
		ext[2] = tolower(ext[2]);

		if (strncmp(ext, "txt", 3) != 0) {
			cout << "Invalid path" << endl;
			return 1;
		}
	}
	else {
		strcat_s(fileName, 260, ".txt");
	}

	ifstream fin;
	fin.open(fileName, ios_base::binary);

	if (!fin.is_open()) {
		cout << "Can't open file" << endl;
		return 1;
	}

	fin.seekg(0, ios_base::_Seekend);
	size_t size = fin.tellg();
	fin.seekg(0, ios_base::_Seekbeg);

	char* buf = new char[size];
	fin.read(buf, size);
	fin.close();

	char str[64];
	cin.getline(str, 64);

	char* found = buf - 1;
	uint16_t cnt = -1;

	do {
		++cnt;
		++found;
		found = strstr(found, str);
	} while (found);

	delete[] buf;
	cout << cnt << " occurrences found" << endl;
	cin.get();

	return 0;
}