Problem p02852 (C++)

Buggy submission (status: Runtime Error):
#include <bits/stdc++.h>
using namespace std;
#define int long long
#define ll long long
#define P pair<int, int>
#define fi first
#define se second
#define rep(i, n) for (int i = 0; i < n; i++)
#define INF 1000000000000000000
#define MOD 1000000007
#define all(v) v.begin(), v.end()
#define pb push_back
int dx[] = {0, 1, 0, -1}, dy[] = {1, 0, -1, 0};
int kaijo[2000010];
struct edge {
  int to, cost;
};
int gcd(int a, int b) {
  if (b == 0)
    return a;
  return gcd(b, a % b);
}
int lcm(int a, int b) { return a / gcd(a, b) * b; }
bool prime(int a) {
  if (a == 1)
    return false;
  for (int i = 2; i * i <= a; i++) {
    if (a % i == 0)
      return false;
  }
  return true;
}
void init_fact() {
  kaijo[0] = 1;
  for (int i = 1; i <= 2000000; i++) {
    kaijo[i] = kaijo[i - 1] * i;
    kaijo[i] %= MOD;
  }
}
int modpow(int a, int b) {
  if (b == 0)
    return 1;
  if (b % 2)
    return modpow(a, b - 1) * a % MOD;
  int memo = modpow(a, b / 2);
  return memo * memo % MOD;
}
int comb(int a, int b) {
  if (!kaijo[0])
    init_fact();
  return kaijo[a] * modpow(kaijo[a - b], MOD - 2) % MOD *
         modpow(kaijo[b], MOD - 2) % MOD;
}
int inv(int x) {
  x = modpow(x, MOD - 2);
  return x;
}
bool kosa(double ax, double ay, double bx, double by, double cx, double cy,
          double dx, double dy) {
  double ta = (cx - dx) * (ay - cy) + (cy - dy) * (cx - ax);
  double tb = (cx - dx) * (by - cy) + (cy - dy) * (cx - bx);
  double tc = (ax - bx) * (cy - ay) + (ay - by) * (ax - cx);
  double td = (ax - bx) * (dy - ay) + (ay - by) * (ax - dx);
  return tc * td < 0 && ta * tb < 0;
}
double dist(double ax, double ay, double bx, double by) {
  return sqrt((bx - ax) * (bx - ax) + (ay - by) * (ay - by));
}
int n, m, now;
string s;
vector<int> ans;
signed main() {
  cin >> n >> m >> s;
  now = n;
  while (now) {
    for (int i = now - m; i < now; i++) {
      if (s[i] == '0') {
        ans.pb(now - i);
        now = i;
        goto ok;
      }
    }
    puts("-1");
    return 0;
  ok:;
  }
  reverse(all(ans));
  for (int i : ans) {
    cout << i << " ";
  }
  cout << endl;
  return 0;
}


Fixed submission:
#include <bits/stdc++.h>
using namespace std;
#define int long long
#define ll long long
#define P pair<int, int>
#define fi first
#define se second
#define rep(i, n) for (int i = 0; i < n; i++)
#define INF 1000000000000000000
#define MOD 1000000007
#define all(v) v.begin(), v.end()
#define pb push_back
int dx[] = {0, 1, 0, -1}, dy[] = {1, 0, -1, 0};
int kaijo[2000010];
struct edge {
  int to, cost;
};
int gcd(int a, int b) {
  if (b == 0)
    return a;
  return gcd(b, a % b);
}
int lcm(int a, int b) { return a / gcd(a, b) * b; }
bool prime(int a) {
  if (a == 1)
    return false;
  for (int i = 2; i * i <= a; i++) {
    if (a % i == 0)
      return false;
  }
  return true;
}
void init_fact() {
  kaijo[0] = 1;
  for (int i = 1; i <= 2000000; i++) {
    kaijo[i] = kaijo[i - 1] * i;
    kaijo[i] %= MOD;
  }
}
int modpow(int a, int b) {
  if (b == 0)
    return 1;
  if (b % 2)
    return modpow(a, b - 1) * a % MOD;
  int memo = modpow(a, b / 2);
  return memo * memo % MOD;
}
int comb(int a, int b) {
  if (!kaijo[0])
    init_fact();
  return kaijo[a] * modpow(kaijo[a - b], MOD - 2) % MOD *
         modpow(kaijo[b], MOD - 2) % MOD;
}
int inv(int x) {
  x = modpow(x, MOD - 2);
  return x;
}
bool kosa(double ax, double ay, double bx, double by, double cx, double cy,
          double dx, double dy) {
  double ta = (cx - dx) * (ay - cy) + (cy - dy) * (cx - ax);
  double tb = (cx - dx) * (by - cy) + (cy - dy) * (cx - bx);
  double tc = (ax - bx) * (cy - ay) + (ay - by) * (ax - cx);
  double td = (ax - bx) * (dy - ay) + (ay - by) * (ax - dx);
  return tc * td < 0 && ta * tb < 0;
}
double dist(double ax, double ay, double bx, double by) {
  return sqrt((bx - ax) * (bx - ax) + (ay - by) * (ay - by));
}
int n, m, now;
string s;
vector<int> ans;
signed main() {
  cin >> n >> m >> s;
  now = n;
  while (now) {
    for (int i = max(0ll, now - m); i < now; i++) {
      if (s[i] == '0') {
        ans.pb(now - i);
        now = i;
        goto ok;
      }
    }
    puts("-1");
    return 0;
  ok:;
  }
  reverse(all(ans));
  for (int i : ans) {
    cout << i << " ";
  }
  cout << endl;
  return 0;
}