#define _USE_MATH_DEFINES
#include <bits/stdc++.h>
using namespace std;
#define FOR(i,m,n) for(int i=(m);i<(n);++i)
#define REP(i,n) FOR(i,0,n)
#define ALL(v) (v).begin(),(v).end()
using ll = long long;
constexpr int INF = 0x3f3f3f3f;
constexpr long long LINF = 0x3f3f3f3f3f3f3f3fLL;
constexpr double EPS = 1e-8;
constexpr int MOD = 998244353;
// constexpr int MOD = 1000000007;
constexpr int DY4[]{1, 0, -1, 0}, DX4[]{0, -1, 0, 1};
constexpr int DY8[]{1, 1, 0, -1, -1, -1, 0, 1};
constexpr int DX8[]{0, -1, -1, -1, 0, 1, 1, 1};
template <typename T, typename U>
inline bool chmax(T& a, U b) { return a < b ? (a = b, true) : false; }
template <typename T, typename U>
inline bool chmin(T& a, U b) { return a > b ? (a = b, true) : false; }
struct IOSetup {
  IOSetup() {
    std::cin.tie(nullptr);
    std::ios_base::sync_with_stdio(false);
    std::cout << fixed << setprecision(20);
  }
} iosetup;

string pyramid(const string& s) {
  const int n = s.length();
  string t = "";
  FOR(i, 1, n) t += (s[i - 1] == '1' && s[i] == '1' ? '0' : '1');
  return t;
}

int main() {
  int n, k; string s; cin >> n >> k >> s;
  s = pyramid(s);
  k = n - k - 1;
  const int l = k / 2;
  REP(_, 2) {
    s.erase(prev(s.end(), l), s.end());
    reverse(ALL(s));
  }
  k -= l * 2;
  if (k == 1) s = pyramid(s);
  cout << s << '\n';
  return 0;
}