#include<bits/stdc++.h> using namespace std; const int N = 1e6 + 5; int n, d, m; pair < int, int > a[N]; inline bool check(int x){ int i = 1, day = 0; while(i <= m){ day += 1; int j = i; while(j <= min(m, i + x - 1) && day >= a[j].first){ if(a[j].first + d < day){ return false; } j += 1; } i = j; } return true; } int main(){ ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0); cin >> n >> d >> m; for(int i = 1; i <= m; i++){ cin >> a[i].first; a[i].second = i; } sort(a + 1, a + m + 1); int l = 1, r = m; while(l < r){ int mid = (r + l) >> 1; if(check(mid)){ r = mid; } else{ l = mid + 1; } } cout << l << "\n"; int i = 1, day = 0; for(int it = 1; it <= n; it++){ day += 1; int j = i; while(j <= min(m, i + l - 1) && day >= a[j].first){ cout << a[j].second << " "; j += 1; } cout << "0\n"; i = j; } }