/* * Author: Nonoze * Created: Monday 15/12/2025 */ #include <bits/stdc++.h> using namespace std; #ifndef DEBUG #define dbg(...) #endif // #define cout cerr << "OUT: " #define endl '\n' #define endlfl '\n' << flush #define quit(x) return (void)(cout << x << endl) template<typename T> void read(T& x) { cin >> x; } template<typename T1, typename T2> void read(pair<T1, T2>& p) { read(p.first), read(p.second); } template<typename T> void read(vector<T>& v) { for (auto& x : v) read(x); } template<typename T1, typename T2> void read(T1& x, T2& y) { read(x), read(y); } template<typename T1, typename T2, typename T3> void read(T1& x, T2& y, T3& z) { read(x), read(y), read(z); } template<typename T1, typename T2, typename T3, typename T4> void read(T1& x, T2& y, T3& z, T4& zz) { read(x), read(y), read(z), read(zz); } template<typename T> void print(vector<T>& v) { for (auto& x : v) cout << x << ' '; cout << endl; } #define sz(x) (int)(x.size()) #define all(x) (x).begin(), (x).end() #define rall(x) (x).rbegin(), (x).rend() #define make_unique(v) sort(all(v)), v.erase(unique(all(v)), (v).end()) #define pb push_back #define mp(a, b) make_pair(a, b) #define fi first #define se second #define cmin(a, b) a = min(a, b) #define cmax(a, b) a = max(a, b) #define YES cout << "YES" << endl #define NO cout << "NO" << endl #define QYES quit("YES") #define QNO quit("NO") #define int long long #define double long double const int inf = numeric_limits<int>::max() / 4; mt19937 rng(chrono::steady_clock::now().time_since_epoch().count()); const int MOD = 1e9+7, LOG=20; void solve(); signed main() { ios::sync_with_stdio(0); cin.tie(0); int tt=1; // cin >> tt; while(tt--) solve(); return 0; } int idx(char c) { if (c=='J') return 0; if (c=='O') return 1; return 2; } int n, k, m, q; vector<int> a; void solve() { read(n, k); string s; read(s); vector<vector<int>> pre(3, vector<int>(n, 0)), pos(3); for (int i=0; i<n; i++) { for (int j=0; i && j<3; j++) pre[j][i] = pre[j][i-1]; pre[idx(s[i])][i]++; pos[idx(s[i])].pb(i); } int cnt0=0, cnt1=0, cnt2=0; for (int i=0; i<n; i++) { if (s[i]=='J') cnt0++; if (cnt0>=k && s[i]=='O') cnt1++; if (cnt1>=k && s[i]=='I') cnt2++; } if (cnt2<k) quit(-1); int ans=sz(s)-3*k; for (int i=0; i<=cnt0-k; i++) { int beg0=pos[0][i], end0=pos[0][i+k-1]; auto it1=lower_bound(all(pos[1]), end0+1); if (it1==pos[1].end() || distance(pos[1].begin(), it1)+k-1>=sz(pos[1])) continue; int beg1=*(it1), end1=pos[1][distance(pos[1].begin(), it1)+k-1]; auto it2=lower_bound(all(pos[2]), end1+1); if (it2==pos[2].end() || distance(pos[2].begin(), it2)+k-1>=sz(pos[2])) continue; int beg2=*(it2), end2=pos[2][distance(pos[2].begin(), it2)+k-1]; int cur=end2-beg0+1; cmin(ans, cur-3*k); } cout << ans << endl; }