#include <bits/stdc++.h> #define f0(i, n) for(int i=(0); i<(n); i++) #define f1(i, n) for(int i=(1); i<=(n); i++) using namespace std; typedef long long ll; const int N = 1000002; int n, d, m, dd[N]; pair <int, int> a[N]; bool check(int x){ f1(i, n) dd[i] = 0; bool ok = 1; for(int i = m; i >= 1; i--){ ok = 0; for(int j = a[i].second; j >= a[i].first; j--){ if(dd[j] < x){ dd[j]++; ok = 1; break; } } if(!ok) return 0; } return 1; } int main(){ ios_base::sync_with_stdio(0); cin >> n >> d >> m; f1(i, m){ int x; cin >> x; a[i] = make_pair(i, i + d - 1); } int l = 0, r = m; sort(a + 1, a + n + 1, [&](pair <int, int> a1, pair <int, int> a2){ if(a1.second != a2.second) return a1.second < a2.second; return a1.first < a2.first; }); int ans = m; while(l <= r){ int mid = (l + r)/2; if(check(mid)) r = mid - 1, ans = mid; else l = mid + 1; } cout << ans; }