# | Time | Username | Problem | Language | Result | Execution time | Memory |
---|---|---|---|---|---|---|---|
763470 | raysh07 | 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 "fish.h"
#include <bits/stdc++.h>
using namespace std;
#define INF (long long)(1e18)
const int N = 1e5 + 69;
vector <int> ok[N];
map <int, long long> a[N];
map <int, long long> dp[N][2];
vector <int> opt[N];
long long val(int i, int j){
int idx = upper_bound(ok[i].begin(), ok[i].end(), j) - ok[i].begin() - 1;
assert(idx >= 0);
return a[i][ok[i][idx]];
// }
long long max_weights(int n, int m, vector<int> x, vector<int> y, vector<int> w) {
for (int i = 0; i < m; i++){
a[x[i] + 1][y[i] + 1] = w[i];
ok[x[i] + 1].push_back(y[i] + 1);
}
ok[0].push_back(0);
a[0][0] = 0;
ok[n + 1].push_back(0);
a[n + 1][0] = 0;
ok[n + 2].push_back(0);
a[n + 2][0] = 0;
for (int i = 0; i < n; i++){
a[i + 1][0] = 0;
ok[i + 1].push_back(0);
sort(ok[i + 1].begin(), ok[i + 1].end());
long long v = 0;
for (auto &[x, y] : a[i + 1]){
v += y;
y = v;
}
}
dp[0][1][0] = dp[0][0][0] = 0; //0, 1 --> not processed / processed
opt[0].push_back(0);
for (int i = 1; i <= n + 1; i++){
for (int x : ok[i - 1]) opt[i].push_back(x);
for (int x : ok[i + 1]) opt[i].push_back(x);
sort(opt[i].begin(), opt[i].end());
opt[i].erase(unique(opt[i].begin(), opt[i].end()), opt[i].end());
for (int j : opt[i]){
dp[i][0][j] = dp[i][1][j] = -INF;
}
if (i != (n + 1)){
for (int j : opt[i]){
if (j == 0) continue;
dp[i][0][j] = max(dp[i][0][j], dp[i - 1][0][0] + val(i - 1, j) - val(i, j));
dp[i][0][j] = max(dp[i][0][j], dp[i - 1][1][0] - val(i, j));
}
long long mx = -INF;
int pt = 1;
for (int j : opt[i]){
if (j == 0) continue;
while (pt != opt[i - 1].size() && opt[i - 1][pt] <= j){
mx = max(mx, dp[i - 1][0][opt[i - 1][pt]]);
pt++;
}
dp[i][0][j] = max(dp[i][0][j], mx - val(i, j) + val(i - 1, j));
}
mx = -INF;
pt = opt[i - 1].size() - 1;
for (int j : opt[i]){
if (j == 0) continue;
while (pt != 0 && opt[i - 1][pt] >= j){
mx = max(mx, dp[i - 1][1][opt[i - 1][pt]]);
pt--;
}
dp[i][1][j] = max(dp[i][1][j], mx - val(i, j) + val(i + 1, j));
}
for (int j : opt[i]){
if (j == 0) continue;
dp[i][1][j] = max(dp[i][1][j], dp[i][0][j] + val(i, j) + val(i + 1, j));
}
}
for (int j : opt[i - 1]){
if (j == 0) continue;
dp[i][0][0] = max(dp[i][0][0], dp[i - 1][1][j] - val(i, j));
dp[i][1][0] = max(dp[i][1][0], dp[i - 1][1][j]);
}
dp[i][0][0] = max(dp[i][0][0], dp[i - 1][0][0]);
dp[i][0][0] = max(dp[i][0][0], dp[i - 1][1][0]);
}
long long ans = -INF;
ans = max(ans, dp[n + 1][0][0]);
ans = max(ans, dp[n + 1][1][0]);
return ans;
}
// int main(){
// int n, m; cin >> n >> m;
// vector <int> a(m), b(m), c(m);
// for (auto &x : a) cin >> x;
// for (auto &x : b) cin >> x;
// for (auto &x : c) cin >> x;
// cout << max_weights(n, m, a, b, c) << "\n";
// return 0;
// }