#include <bits/stdc++.h>

using i64 = long long;

std::vector<bool> naive(std::vector<bool> s) {
    const int N = (int)s.size();
    std::vector<bool> new_s(N - 1);
    for (int i = 0; i < N - 1; ++i) new_s[i] = (s[i] and s[i + 1]) ? false : true;
    return new_s;
}

int main() {
    int N, K; std::cin >> N >> K;
    std::vector<bool> S(N);
    for (int i = 0; i < N; ++i) {
        char c; std::cin >> c;
        S[i] = (bool)(c == '1');
    }

    // 1
    if (N - K < 10) {
        while (K != N) {
            S = naive(S);
            ++K;
        }
    } else {
        int c = N - K - 1;
        S = naive(S);
        if (c % 2 == 1) S = naive(S);
        c /= 2;
        std::vector<bool> ans;
        for (int i = c; (int)ans.size() != K; ++i) ans.push_back(S[i]);
        S = ans;
    }
    for (const auto e : S) std::cout << e;
    std::cout << std::endl;
}