// #include <bits/stdc++.h> #include <iostream> #include <cmath> #include <algorithm> #include <map> #include <vector> #include <iomanip> #include <string> #include <queue> #include <set> #include <deque> #include <numeric> #include <stack> #include <chrono> using namespace std; void fast_io(){ // freopen("", "r", stdin); // freopen("", "w", stdout); ios::sync_with_stdio(0); cin.tie(); cout.tie(); cout << setprecision(9); } #define int long long #define endl '\n' #define all(v) (v).begin(), (v).end() #define rall(v) (v).rbegin(), (v).rend() #define fi first #define se second void solve() { int n, k; cin >> n >> k; string s; cin >> s; s = "." + s; int pref[n + 1] = {}; vector<int> idxj, idxo, idxi; for (int i = 1; i <= n; i++){ if (s[i] == 'J') idxj.push_back(i); if (s[i] == 'O') idxo.push_back(i); if (s[i] == 'I') idxi.push_back(i); pref[i] = pref[i - 1] + (s[i] == 'O'); } set<pair<int, int>> S; int m = idxi.size(); for (int i = 0; i < m; i++){ S.insert({pref[idxi[i]], i}); } int ans = 1e18; m = idxj.size(); for (int i = k - 1; i < m; i++){ auto it = S.lower_bound({pref[idxj[i]] + k, 0}); if (it == S.end()) continue; auto [val, idx] = *it; if (idx + k - 1 < (int) idxi.size()) ans = min(ans, idxi[idx + k - 1] - idxj[i - k + 1] + 1); } if (ans == 1e18) ans = 3 * k - 1; cout << ans - 3 * k << endl; return; } signed main() { fast_io(); srand(chrono::steady_clock::now().time_since_epoch().count()); int tc = 1; // cin >> tc; while (tc--) solve(); return 0; }