| # | Time | Username | Problem | Language | Result | Execution time | Memory |
|---|---|---|---|---|---|---|---|
| 1067667 | HorizonWest | 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>
//#include "fish.h"
using namespace std;
#pragma GCC optimize("O3")
#define endl '\n'
#define db double
#define ll long long
#define pb push_back
#define fs first
#define sd second
#define Mod long(1e9 + 7)
#define all(x) x.begin(), x.end()
#define unvisited long(-1)
#define Eps double(1e-9)
#define _for(i, n) for(int i = 0; i < (n); i++)
#define dbg(x) cout << #x ": " << x << endl;
const int Max = 1e6 + 7, Inf = 1e9 + 7;
void print(bool x) { cout << (x ? "YES" : "NO") << endl; }
string tostring (__int128 x)
{
string ans = "";
while(x > 0)
{
ans += (x % 10 + '0');
x /= 10;
}
reverse(all(ans));
return ans;
}
long long max_weights(int n, int m, vector<int> X, vector<int> Y, vector<int> W)
{
vector <vector<pair<ll, ll>>> v(n + 7, vector <pair<ll, ll>> ());
//vector <vector<ll>> v(n, vector <ll> (n+1, 0));
unordered_map <int, unordered_map <int, int>> mp;
for(int i = 0; i < m; i++){
//v[X[i]][Y[i]+1] = W[i];
v[X[i]].push_back({ Y[i] + 1, W[i] });
if(X[i] > 0) v[X[i]-1].push_back({ Y[i] + 1, 0 });
if(X[i] > 1) v[X[i]-2].push_back({ Y[i] + 1, 0 });
if(X[i] < n) v[X[i]+1].push_back({ Y[i] + 1, 0 });
if(X[i] < n) v[X[i]+2].push_back({ Y[i] + 1, 0 });
}
for(int i = 0; i < n; i++)
{
v[i].push_back({ 0, 0 }); sort(all(v[i]));
for(int j = 0; j < (int) v[i].size(); j++){
if (j != 0) v[i][j].sd += v[i][j-1].sd;
mp[i][v[i][j].fs] = j;
}
}
auto C = [&] (int i, int j, int k) -> ll
{
ll ans = 0;
if(i >= 0 && i < n) {
ans = ans + max(0LL, v[i][mp[i][j]].sd - v[i][mp[i][k]].sd);
}
return ans;
};
vector <vector<ll>> dp1, dp2; ll ans = 0;
for(int i = 0; i < n; i++)
{
dp1.push_back(vector <ll> (v[i].size(), 0));
dp2.push_back(vector <ll> (v[i].size(), 0));
for(int j = 0; j < (int) v[i].size(); j++)
{
int hj = v[i][j].fs;
dp1[i][j] = C(i-1, hj, 0) + C(i+1, hj, 0);
dp2[i][j] = C(i-1, hj, 0) + C(i+1, hj, 0);
if(i > 1){
for(int k = 0; k < (int) v[i-2].size(); k++){
int hk = v[i-2][k].fs;
dp1[i][j] = max(dp1[i][j], (i > 1 ? dp2[i-2][k] : 0LL) + C(i-1, hj, hk) + C(i+1, hj, 0));
}
}
if(i > 0){
for(int k = 0; k < (int) v[i-1].size(); k++){
int hk = v[i-1][k].fs;
dp1[i][j] = max(dp1[i][j], (i != 0 ? dp1[i-1][k] : 0) + C(i-1, hj, hk) + C(i+1, hj, 0) - C(i, hk, 0));
}
/*for(int k = 0; k < (int) v[i-1].size(); k++){
int hk = v[i-1][k].fs;
dp2[i][j] = max(dp2[i][j], (i != 0 ? dp1[i-1][k] : 0) - C(i, hj, 0) + C(i+1, hj, 0));
dp2[i][j] = max(dp2[i][j], (i != 0 ? dp2[i-1][k] : 0) - C(i, hj, 0) + C(i+1, hj, 0));
}*/
}
ans = max(ans, max(dp1[i][j], dp2[i][j]));
}
if(i > 0)
{
ll k = v[i-1].size() - 1, mx = 0;
for(int j = (int) v[i].size() - 1; j >= 0; j--)
{
int hj = v[i][j].fs;
for(k; k >= 0; k--){
if(v[i-1][k].fs >= v[i][j].fs){
mx = max(mx, dp1[i-1][k]);
mx = max(mx, dp2[i-1][k]);
} else break;
}
dp2[i][j] = max(dp2[i][j], (i != 0 ? dp1[i-1][k] : 0) - C(i, hj, 0) + C(i+1, hj, 0));
dp2[i][j] = max(dp2[i][j], (i != 0 ? dp2[i-1][k] : 0) - C(i, hj, 0) + C(i+1, hj, 0));
mx = mx + v[i][j].sd;
}
}
}
return ans;
}
int main() {
int N, M;
assert(2 == scanf("%d %d", &N, &M));
std::vector<int> X(M), Y(M), W(M);
for (int i = 0; i < M; ++i) {
assert(3 == scanf("%d %d %d", &X[i], &Y[i], &W[i]));
}
long long result = max_weights(N, M, X, Y, W);
printf("%lld\n", result);
return 0;
}