#include <fmt/ranges.h>

#include <string>

#include <sys/stat.h>

class Solution

{

static constexpr auto makeRomanParser()

{

enum State { Start, Numbers, Invalid };

return [value = 0, state = Start, sign = 1](const char input) mutable -> int32_t {

switch (state) {

case Start:

if (input == ' ') {

return 0;

}

if (input == '-') {

sign = -1;

state = Numbers;

return value;

}

if (input == '+') {

sign = 1;

state = Numbers;

return value;

}

[[fallthrough]];

case Numbers:

if (input >= '0' && input <= '9') {

state = Numbers;

value = static_cast<int32_t>(

std::clamp(static_cast<int64_t>(value) * 10 + sign * (input - '0'),

static_cast<int64_t>(INT_MIN),

static_cast<int64_t>(INT_MAX)));

return value;

}

[[fallthrough]];

case Invalid:

state = Invalid;

return value;

default:

return 0;

}

};

}

public:

int myAtoi(std::string s)

{

auto parser = makeRomanParser();

int result = 0;

for (const auto &c : s) {

result = parser(c);

}

return result;

}

};

int main()

{

Solution sol;

// test cases

std::string s1 = "42";

std::string s2 = " -042";

std::string s3 = "-1337c0d3";

std::string s4 = "0-1";

std::string s5 = "words and 987";

std::string s6 = "-91283472332";

std::string s7 = "+1";

for (auto s : {s1, s2, s3, s4, s5, s6, s7}) {

fmt::print("Before: [{}] After: [{}]\n", s, sol.myAtoi(s));

}

}