| # | Time | Username | Problem | Language | Result | Execution time | Memory |
|---|---|---|---|---|---|---|---|
| 672999 | pls33 | Catfish Farm (IOI22_fish) | C++17 | 0 ms | 0 KiB |
This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include <bits/stdc++.h>
#ifdef ONLINE_JUDGE
#include "fish.h"
#endif
using namespace std;
#pragma region dalykai
using p32 = pair<int, int>;
using p32u = pair<uint32_t, uint32_t>;
using p64 = pair<int64_t, int64_t>;
using p64u = pair<uint64_t, uint64_t>;
using vi16 = vector<int16_t>;
using vi16u = vector<uint16_t>;
using vi32 = vector<int>;
using vi32u = vector<uint32_t>;
using vi64 = vector<int64_t>;
using vi64u = vector<uint64_t>;
using vp32 = vector<p32>;
using vp32u = vector<p32u>;
using vp64 = vector<p64>;
using vp64u = vector<p64u>;
using vvi32 = vector<vi32>;
using vvi32u = vector<vi32u>;
using vvi64 = vector<vi64>;
using vvi64u = vector<vi64u>;
using vvp32 = vector<vp32>;
using vvp32u = vector<vp32u>;
using vvp64 = vector<vp64>;
using vvp64u = vector<vp64u>;
#pragma endregion
void update(int64_t val, p32 fish, vvi64 &vect)
{
vect[fish.first][fish.second] = max(vect[fish.first][fish.second], val);
}
int64_t weight_sum(int i, int j, vvi64 &prefix, int row)
{
if (i == -1)
{
return 0;
}
int64_t sum = prefix[row][j];
if (i)
{
sum -= prefix[row][i - 1];
}
return sum;
}
int64_t new_weight(p32 lhs, p32 rhs, vvi64 &prefix){
long left = rhs.first > 0
? weight_sum(0, rhs.second, prefix, rhs.first - 1)
: 0;
long right = (rhs.first + 1 < prefix.size())
? weight_sum(0, rhs.second, prefix, rhs.first + 1)
: 0;
if (lhs.first == -1)
{
return left + right;
}
if (rhs.first - lhs.first > 2)
{
return left + right;
}
if (rhs.first - lhs.first == 2)
{
if (lhs.second >= rhs.second)
{
return right;
}
left -= weight_sum(0, lhs.second, prefix, rhs.first - 1);
return left + right;
}
if (lhs.second > rhs.second)
{
left = -weight_sum(0, rhs.second, prefix, rhs.first);
return left + right;
}
left -= weight_sum(0, lhs.second, prefix, rhs.first) +
weight_sum(0, lhs.second, prefix, rhs.first - 1);
return left + right;
}
long long max_weights(int N, int M,
std::vector<int> X,
std::vector<int> Y,
std::vector<int> W)
{
vp32 fish;
vvi64 prefix(N, vi64(N));
int max_y = 0;
for (int i = 0; i < M; i++)
{
max_y = max(max_y, Y[i]);
prefix[X[i]][Y[i]] = W[i];
if (X[i])
{
fish.push_back({X[i] - 1, Y[i]});
}
if (X[i] < N - 1)
{
fish.push_back({X[i] + 1, Y[i]});
}
}
max_y++;
for (auto &row : prefix)
{
for (int i = 1; i < (int)row.size(); i++)
{
row[i] += row[i - 1];
}
}
sort(fish.begin(), fish.end());
auto it = unique(fish.begin(), fish.end());
fish.erase(it, fish.end());
vvi64 decrease(N, vi64(max_y + 1));
vvi64 increase = decrease;
for (auto &f : fish)
{
int64_t initial = new_weight(p32(-1, -1), f, prefix);
update(initial, f, increase);
update(initial, f, decrease);
for(int i = 0; i < f.first; i++){
for (int j = 0; j < N; j++)
{
int64_t prev = new_weight(p32(i, j), f, prefix);
if(i == f.first - 1){
if(j < f.second){
update(prev + increase[i][j], f, increase);
}
else {
update(prev + decrease[i][j], f, decrease);
}
}
else {
prev += max(increase[i][j], decrease[i][j]);
update(prev, f, increase);
update(prev, f, decrease);
}
}
}
}
int64_t res = 0;
for (int i = 0; i < (int)increase.size(); i++)
{
for (int j = 0; j < (int)increase[0].size(); j++)
{
res = max({res, increase[i][j], decrease[i][j]});
}
}
return res;
}
#ifndef ONLINE_JUDGE
int main(int argc, char** argv) {
int N, M;
cin >> N >> M;
std::vector<int> X(M), Y(M), W(M);
for (int i = 0; i < M; ++i) {
cin >> X[i] >> Y[i] >> W[i];
}
long long result = max_weights(N, M, X, Y, W);
cout << result << '\n';
return 0;
}
#endif