#ifndef _DEBUG #include #else #include "bits/stdc++.h" #endif using namespace std; using ll = long long; using ld = long double; using VI = vector; using VL = vector; using VS = vector; template using PQ = priority_queue, greater>; #define FOR(i,a,n) for(int i=(a);i<(n);++i) #define eFOR(i,a,n) for(int i=(a);i<=(n);++i) #define rFOR(i,a,n) for(int i=(n)-1;i>=(a);--i) #define erFOR(i,a,n) for(int i=(n);i>=(a);--i) #define SORT(a) sort(a.begin(),a.end()) #define rSORT(a) sort(a.rbegin(),a.rend()) #define fSORT(a,f) sort(a.begin(),a.end(),f) #define all(a) a.begin(),a.end() #define out(y,x) ((y)<0||h<=(y)||(x)<0||w<=(x)) #define tp(a,i) get(a) #ifdef _DEBUG #define line cout << "-----------------------------\n" #define stop system("pause") #endif constexpr ll INF = 1000000000; constexpr ll LLINF = 1LL << 60; constexpr ll mod = 1000000007; constexpr ll MOD = 998244353; constexpr ld eps = 1e-10; constexpr ld pi = 3.1415926535897932; templateinline bool chmax(T& a, const T& b) { if (a < b) { a = b; return true; }return false; } templateinline bool chmin(T& a, const T& b) { if (a > b) { a = b; return true; }return false; } inline void init() { cin.tie(nullptr); cout.tie(nullptr); ios::sync_with_stdio(false); cout << fixed << setprecision(15); } templateinline istream& operator>>(istream& is, vector& v) { for (auto& a : v)is >> a; return is; } templateinline istream& operator>>(istream& is, pair& p) { is >> p.first >> p.second; return is; } templateinline vector vec(size_t a) { return vector(a); } templateinline vector defvec(T def, size_t a) { return vector(a, def); } templateinline auto vec(size_t a, Ts... ts) { return vector(ts...))>(a, vec(ts...)); } templateinline auto defvec(T def, size_t a, Ts... ts) { return vector(def, ts...))>(a, defvec(def, ts...)); } templateinline void print(const T& a) { cout << a << "\n"; } templateinline void print(const T& a, const Ts&... ts) { cout << a << " "; print(ts...); } templateinline void print(const vector& v) { for (int i = 0; i < v.size(); ++i)cout << v[i] << (i == v.size() - 1 ? "\n" : " "); } templateinline void print(const vector>& v) { for (auto& a : v)print(a); } inline string reversed(const string& s) { string t = s; reverse(all(t)); return t; } templateinline T sum(const vector& a, int l, int r) { return a[r] - (l == 0 ? 0 : a[l - 1]); } templateinline void END(T s) { print(s); exit(0); } void END() { exit(0); } template class SegmentTree { using T = typename Op::T; int len, n; vector dat; public: SegmentTree(const int _n) : n(_n) { for (len = 1; len < n; len <<= 1); dat.resize(len << 1, Op::unit); } SegmentTree(const vector& v) : n(v.size()) { for (len = 1; len < n; len <<= 1); dat.resize(len << 1, Op::unit); for (int i = 0; i < n; ++i)dat[i + len] = v[i]; for (int i = len - 1; 0 < i; --i) dat[i] = Op::merge(dat[i << 1], dat[i << 1 | 1]); } inline void update(int idx, const T a) { idx += len; dat[idx] = Op::update(dat[idx], a); for (idx >>= 1; 0 < idx; idx >>= 1) dat[idx] = Op::merge(dat[idx << 1], dat[idx << 1 | 1]); } inline T value(int l, int r) { T vl = Op::unit, vr = Op::unit; for (l += len, r += len; l < r; l >>= 1, r >>= 1) { if (l & 1)vl = Op::merge(vl, dat[l++]); if (r & 1)vr = Op::merge(dat[--r], vr); } return Op::merge(vl, vr); } inline T operator[](int idx) { return dat[idx + len]; } }; template struct node { using T = Type; inline static T unit = 0; inline static T merge(T vl, T vr) { return vl + vr; } inline static T update(T vl, T vr) { return vl + vr; } }; int main() { init(); int n, k; cin >> n >> k; string s; cin >> s; s = "o" + s; SegmentTree> dp(n + 1); rFOR(i, 0, n) { if (s[i] == 'o' && dp.value(i + 1, min(n + 1, i + k + 1)) == 0)dp.update(i, 1); } eFOR(i, 1, k)if (dp[i])END(i); END(0); return 0; }