#include <bits/stdc++.h>
int main() {
std::ios::sync_with_stdio(false);
std::cin.tie(0);
int numDay, limitDelay, numRequest;
std::cin >> numDay >> limitDelay >> numRequest;
std::vector<int> dayStartRequest(numRequest);
for (int &day : dayStartRequest) {
std::cin >> day;
}
std::vector<int> order(numRequest);
iota(order.begin(), order.end(), 0);
sort(order.begin(), order.end(), [&](int indexLeft, int indexRight) {
return dayStartRequest[indexLeft] > dayStartRequest[indexRight];
});
sort(dayStartRequest.begin(), dayStartRequest.end(), std::greater<int>());
int low = 1, high = numRequest, needMachine = high;
while (low <= high) {
int middle = low + ((high - low + 1) >> 1);
int maxDelay = 0, day = 1;
for (int index = numRequest - 1; index >= 0; ) {
int machine = 0;
while (index >= 0 && day >= dayStartRequest[index] && machine < middle) {
maxDelay = std::max(maxDelay, day - dayStartRequest[index]);
index--;
machine++;
}
day++;
}
if (maxDelay <= limitDelay) {
needMachine = middle;
high = middle - 1;
} else {
low = middle + 1;
}
}
std::cout << needMachine << '\n';
std::vector<std::vector<int>> schedule(numDay);
int day = 1;
for (int index = numRequest - 1; index >= 0; ) {
int machine = 0;
while (index >= 0 && day >= dayStartRequest[index] && machine < needMachine) {
schedule[day - 1].emplace_back(order[index] + 1);
index--;
machine++;
}
day++;
}
for (int day = 0; day < numDay; day++) {
for (const int &index : schedule[day]) {
std::cout << index << ' ';
}
std::cout << 0 << '\n';
}
return 0;
}
