up08-2 (automata)

#include <iostream>
#include <cctype>

int parse(const char c)
{
    size_t size = 1;
    bool find_one = false;

    bool find_pattern = true;
    bool flag_zero_pattern = true;

    int k = 1;
    int m = 0;

    int counter_k = 0;
    int counter_m = 0;
    bool flag_zero = true;

    if (c != '0') {
        return 0;
    }

    char i;
    while ((i = std::cin.get())) {
        if (std::isspace(i) || i == EOF) {
            std::cin.unget();
            break;
        }
        size++;
        if (find_pattern) {
            if (i == '0') {
                if (flag_zero_pattern) {
                    k++;
                } else {
                    find_pattern = false;
                    std::cin.unget();
                    size--;
                }
            } else if (i == '1') {
                find_one = true;
                m++;
                flag_zero_pattern = false;
            } else {
                return 0;
            }
        } else {
            if (i == '0') {
                if (counter_k < k && flag_zero) {
                    counter_k++;
                } else {
                    return 0;
                }
            } else if (i == '1') {
                if (counter_k == k && flag_zero) {
                    flag_zero = false;
                }

                if (counter_m < m && !flag_zero) {
                    counter_m++;
                } else {
                    return 0;
                }

                if (counter_m == m && !flag_zero) {
                    counter_k = 0;
                    counter_m = 0;
                    flag_zero = true;
                }
            }
        }
    }
    return find_one && !(size % (k + m));
}

int main()
{
    char c;
    while ((c = std::cin.get()) != EOF) {
        if (std::isspace(c)) {
            continue;
        } else {
            int ans = parse(c);
            std::cout << ans << std::endl;
            while ((c = std::cin.get())) {
                if (isspace(c)) {
                    break;
                } else if (c == EOF) {
                    return 0;
                }
            }
        }
    }
}