Code: https://github.com/Loki-Astari/Puzzle/tree/master/wc
Challenge: https://codingchallenges.fyi/challenges/challenge-wc/
wc.cpp
#include <cstddef>
#include <fstream>
#include <vector>
#include <string>
#include <iostream>
/*
* Command line options.
* If no options are specified then any is true and we print all values.
*/
struct Options
{
bool any = true;
bool lines = false;
bool words = false;
bool chars = false;
bool bytes = false;
};
/*
* Collect values from a file.
*/
struct Result
{
std::size_t lines = 0;
std::size_t words = 0;
std::size_t chars = 0;
std::size_t bytes = 0;
};
Result getData(std::istream& file)
{
Result result;
int c = file.get();
bool newLine = true;
bool inWord = !std::isspace(c);
for (; c != std::char_traits<char>::eof(); c = file.get()) {
// A line must have at least one character on it.
// The new line character counts as a character for this purpose.
if (newLine == true) {
newLine = false;
result.lines += 1;
}
if (c == '\n') {
newLine = true;
}
// Words are "white space" separated.
// Increment the counter when we hit a space when inside a word.
bool isSpace = std::isspace(c);
if (inWord && isSpace) {
inWord = false;
result.words += 1;
}
else if (!inWord && !isSpace) {
inWord = true;
}
// Ignore extra characters in multi byte character;
if ((c & 0xC0) != 0x80) {
result.chars += 1;
}
// Increment for each char read from the stream
result.bytes += 1;
}
// We are in a word that has not been counted.
if (inWord) {
result.words += 1;
}
return result;
}
void display(std::istream& file, std::string const& fileName, Options const& options)
{
Result data = getData(file);
std::cout << "\t";
if (options.any || options.lines) {
std::cout << data.lines << "\t";
}
if (options.any || options.words) {
std::cout << data.words << "\t";
}
if (options.any || options.chars) {
std::cout << data.chars << "\t";
}
if (options.any || options.bytes) {
std::cout << data.bytes << "\t";
}
std::cout << fileName << "\n";
}
int main(int argc, char* argv[])
{
Options options;
std::vector<std::string> files;
int loop = 1;
for (; loop < argc; ++loop) {
/*
* If this is not a flag then we have reached the files.
*/
if (argv[loop][0] != '-') {
break;
}
/* Allow old style unix flags */
for (int flag = 1; argv[loop][flag]; ++flag) {
if (argv[loop][flag] == 'l') {
options.any = false;
options.lines = true;
}
else if (argv[loop][flag] == 'w') {
options.any = false;
options.words = true;
}
else if (argv[loop][flag] == 'm') {
options.any = false;
options.chars = true;
}
else if (argv[loop][flag] == 'c') {
options.any = false;
options.bytes = true;
}
else {
std::cerr << "Usage: wc [-lwmc] <files>*\n";
return 1;
}
}
}
/* Any remaining command line values are files */
for (; loop < argc; ++loop) {
files.emplace_back(argv[loop]);
}
/* If no files are explicitly set then use std::cin */
if (files.size() == 0) {
display(std::cin, "", options);
}
/* Loop over all the specified files */
for (auto fileName: files) {
std::ifstream file(fileName);
if (!file) {
std::cout << "Unknown file: " << fileName << "\n";
}
else {
display(file, fileName, options);
}
}
}
