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/* ************************************************************************** */
/* */
/* ::: :::::::: */
/* main.cpp :+: :+: :+: */
/* +:+ +:+ +:+ */
/* By: charles <charles.cabergs@gmail.com> +#+ +:+ +#+ */
/* +#+#+#+#+#+ +#+ */
/* Created: 2020/04/16 10:54:10 by charles #+# #+# */
/* Updated: 2020/12/13 17:11:08 by charles ### ########.fr */
/* */
/* ************************************************************************** */
#include <iostream>
#include <iomanip>
#include <sstream>
#include <string>
#include <cctype>
#include <climits>
#include <cmath>
bool is_char(std::string input)
{
return input.length() == 3 && input[0] == '\'' && input[2] == '\'';
}
bool is_int(std::string input)
{
if (input[0] == '-' || input[0] == '+')
input = input.substr(1);
for (size_t i = 0; i < input.length(); i++)
if (!isdigit(input[i]))
return false;
return true;
}
bool is_double(std::string input)
{
if (input == "nan" || input == "+inf" || input == "-inf")
return true;
if (input[0] == '-' || input[0] == '+')
input = input.substr(1);
if (input.find('.') == std::string::npos ||
input.find('.') != input.rfind('.') ||
input.find('.') == 0 ||
input.find('.') == input.length() - 1)
return false;
for (size_t i = 0; i < input.length(); i++)
{
if (input[i] == '.')
continue;
if (!isdigit(input[i]))
return false;
}
return true;
}
bool is_float(std::string input)
{
if (input[input.length() - 1] != 'f')
return false;
if (input.find('.') == std::string::npos)
input.insert(input.length() - 1, ".0");
return is_double(input.substr(0, input.length() - 1));
}
int main(int argc, char **argv)
{
if (argc != 2)
{
std::cerr << "Usage: " << argv[0] << " litteral" << std::endl;
return 1;
}
std::string s(argv[1]);
if (s.empty())
{
std::cerr << "Litteral cannot be empty" << std::endl;
return 1;
}
std::cout << std::setprecision(1) << std::fixed;
double x;
if (is_char(s))
x = s[1];
else if (is_int(s))
{
std::stringstream ss(s);
ss >> x;
}
else if (is_float(s))
{
if (s == "nanf")
x = NAN;
else if (s == "+inff")
x = INFINITY;
else if (s == "-inff")
x = -INFINITY;
else
{
std::stringstream ss(s.substr(0, s.length() - 1));
ss >> x;
}
}
else if (is_double(s))
{
if (s == "nan")
x = NAN;
else if (s == "+inf")
x = INFINITY;
else if (s == "-inf")
x = -INFINITY;
else
{
std::stringstream ss(s);
ss >> x;
}
}
else
{
std::cerr << "Litteral `" << s << "` is not valid" << std::endl;
return 1;
}
if (CHAR_MIN <= x && x <= CHAR_MAX && !std::isnan(x) && !std::isinf(x))
{
char c = static_cast<char>(x);
if (std::isprint(c))
std::cout << "char: '" << c << "'" << std::endl;
else
std::cout << "char: Non displayable" << std::endl;
}
else
std::cout << "char: impossible" << std::endl;
if (INT_MIN <= x && x <= INT_MAX && !std::isnan(x) && !std::isinf(x))
std::cout << "int: " << static_cast<int>(x) << std::endl;
else
std::cout << "int: impossible" << std::endl;
std::cout << "float: " << static_cast<float>(x) << 'f' << std::endl;
std::cout << "double: " << x << std::endl;
return 0;
}
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