#include <bits/stdc++.h>
using namespace std;
using ull = unsigned long long;
/*
We check whether all jobs can be scheduled with m machines
such that each job with release day job can be done within
[job, job + d].
*/
bool can_schedule(const vector<pair<ull,int>>& jobs, ull d, ull m) {
ull day = 0;
ull used = 0;
for (auto &[job, _] : jobs) {
// Move forward in time if needed
while (day < job) {
day++;
used = 0;
}
if (day <= job + d) {
used++;
if (used == m) {
day++;
used = 0;
}
} else {
return false;
}
}
return true;
}
void solve(vector<pair<ull,int>> jobs, ull n, ull d) {
ull left = 1;
ull right = jobs.size();
// Check if 1 machine is enough
if (can_schedule(jobs, d, 1)) {
right = 1;
} else {
// Binary search for minimal m
while (left < right - 1) {
ull mid = left + (right - left) / 2;
if (can_schedule(jobs, d, mid))
right = mid;
else
left = mid;
}
}
// Build the actual schedule
map<int, vector<int>> schedule;
ull day = 1;
for (auto &[job, idx] : jobs) {
while (day < job) day++;
schedule[day].push_back(idx + 1);
if (schedule[day].size() == right)
day++;
}
// Output
cout << right << "\n";
for (ull i = 1; i <= n; i++) {
for (int v : schedule[i])
cout << v << " ";
cout << 0 << "\n";
}
}
int main() {
ios::sync_with_stdio(false);
cin.tie(nullptr);
ull n, d, m;
cin >> n >> d >> m;
vector<ull> input(m);
for (ull i = 0; i < m; i++)
cin >> input[i];
vector<pair<ull,int>> jobs;
for (int i = 0; i < (int)m; i++)
jobs.push_back({input[i], i});
sort(jobs.begin(), jobs.end());
solve(jobs, n, d);
return 0;
}
