oj.uz

Submission #1105910

# Submission time Handle Problem Language Result Execution time Memory
1105910 2024-10-28T10:56:45 Z Zero_OP Catfish Farm (IOI22_fish) C++17
53 / 100
 73 ms 32072 KB 
#include <bits/stdc++.h>
#ifndef LOCAL
    #include <fish.h>
#endif // LOCAL

using namespace std;

#define rep(i, l, r) for(int i = (l), _r = (r); i < _r; ++i)
#define FOR(i, l, r) for(int i = (l), _r = (r); i <= _r; ++i)
#define ROF(i, r, l) for(int i = (r), _l = (l); i >= _l; --i)
#define all(v) begin(v), end(v)
#define compact(v) v.erase(unique(all(v)), end(v))
#define sz(v) (int)v.size()
#define dbg(x) "[" #x " = " << (x) << "]"

template<typename T>
bool minimize(T& a, const T& b){
    if(a > b) return a = b, true; return false;
}

template<typename T>
bool maximize(T& a, const T& b){
    if(a < b) return a = b, true; return false;
}

using ll = long long;
using ld = long double;

mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
template<typename T> T random_int(T l, T r){ return uniform_int_distribution<T>(l, r)(rng); }
template<typename T> T random_real(T l, T r){ return uniform_real_distribution<T>(l, r)(rng); }

const int MAX = 3e5 + 5;

int n, m;
struct fish{
    int x, y, w;
} fishes[MAX];

namespace subtask1{
    bool check(){
        rep(i, 0, m) if(fishes[i].x& 1) return false;
        return true;
    }

    ll solve(){
        ll sum = 0;
        rep(i, 0, m){
            if((i > 0) || (i < n - 1)){
                sum += fishes[i].w;
            }
        }
        return sum;
    }
}

namespace subtask2{
    bool check(){
        for(int i = 0; i < m; ++i){
            if(fishes[i].x > 1) return false;
        }
        return true;
    }

    ll sum[3][MAX];
    ll f[3][MAX], g[3][MAX];

    ll solve(){
        memset(f, 0, sizeof(f));
        memset(g, 0, sizeof(g));

        rep(i, 0, m){
            sum[fishes[i].x][fishes[i].y] += fishes[i].w;
        }

        rep(i, 0, 2){
            rep(j, 0, n){
                sum[i][j] += (j > 0 ? sum[i][j - 1] : 0);
            }
        }

        ll ans = max(sum[0][n - 1], sum[1][n - 1]);
        if(n > 2){
            rep(i, 0, n){
                maximize(ans, sum[1][n - 1] - sum[1][i] + sum[0][i]);
            }
        }

        return ans;
    }
}

namespace subtask3{
    bool check(){
        rep(i, 0, m){
            if(fishes[i].y > 0) return false;
        }
        return true;
    }

    ll dp[MAX], s[MAX];

    ll solve(){
        rep(i, 0, m) s[fishes[i].x] = fishes[i].w;

        dp[0] = 0;
        ll res = 0;
        rep(i, 1, n){
            dp[i] = max(dp[i - 1], s[i - 1]);
            if(i >= 2) maximize(dp[i], dp[i - 2] + s[i - 1]);
            if(i >= 3) maximize(dp[i], dp[i - 3] + s[i - 2] + s[i - 1]);
            maximize(res, dp[i] + s[i + 1]);
        }

        return res;
    }
}

namespace subtask45{
    bool check(){
        return n <= 300;
    }

    ll pref[305][305];

    ll solve(){
        rep(i, 0, m){
            pref[fishes[i].x + 1][fishes[i].y + 1] += fishes[i].w;
        }

        FOR(i, 1, n){
            FOR(j, 1, n){
                pref[i][j] += pref[i][j - 1];
            }
        }

        const ll inf = 1e18;
        vector<vector<ll>> f(n + 1, vector<ll>(n + 1, -inf));
        vector<vector<ll>> g(n + 1, vector<ll>(n + 1, -inf));

        /*

        let f[c][r] = the maximum sum of weights if we put a pier (c, r) but we don't consider the fishes (c, r') with r' >= r
            g[c][r] = the maximum sum of weights if we put a pier (c, r) but we consider the fishes (c, r') with r' >= r
        let R[i] the height of pier on column c the we put

        consider when R[i - 1] < R[i] -> it contributes to f[c][r]
        consider when R[i - 1] > R[i] -> it contributes to g[c][r]

        when calculating f[c][r] :
        - consider R[i - 2] > R[i - 1] < R[i]
        - consider R[i - 2] < R[i - 1] < R[i]

        */

        FOR(i, 0, n){
            f[1][i] = g[1][i] = 0;
        }

        FOR(c, 2, n){
            FOR(r, 0, n){
                if(r == 0){
                    maximize(f[c][r], g[c - 1][r]);
                }

                FOR(k, 0, r){
                    maximize(f[c][r], f[c - 1][k] + pref[c - 1][r] - pref[c - 1][k]);
//                    cout << dbg(c) << dbg(r) << dbg(f[c - 1][k] + pref[c - 1][r] + pref[c - 1][k]) << '\n';
                }

                if(c > 2 && r > 0){
                    FOR(k, 1, n){
                        maximize(f[c][r], max(f[c - 2][k], g[c - 2][k]) + pref[c - 1][max(r, k)]);
//                        cout << dbg(c) << dbg(r) << dbg(max(f[c - 2][r], g[c - 2][r]) + pref[c - 1][max(r, k)]) << '\n';
                    }
                }

                FOR(k, r, n){
                    maximize(g[c][r], max(f[c - 1][k], g[c - 1][k]) + pref[c][k] - pref[c][r]);
//                    cout<< dbg(c) << dbg(r) << dbg(max(f[c - 1][k], g[c - 1][k]) + pref[c][k] - pref[c][r]) << '\n';
                }
            }
        }

        ll ans = 0;
        FOR(c, 1, n){
            FOR(r, 1, n){
                maximize(ans, max(f[c][r], g[c][r]) + (c < n ? pref[c + 1][r] : 0));
            }
        }

//        FOR(i, 1, n){
//            FOR(j, 1, n){
//                cout << pref[j][n - i + 1] << " \n"[j == n];
//            }
//        }
//        cout << "F[r][c] : \n";
//        FOR(i, 1, n){
//            FOR(j, 1, n){
//                cout << f[j][n - i + 1] << " \n"[j == n];
//            }
//        }
//
//        cout << '\n' << "G[r][c] : \n";
//        FOR(i, 1, n){
//            FOR(j, 1, n){
//                cout << g[j][n - i + 1] << " \n"[j == n];
//            }
//        }
//        cerr << "subtask 4, 5 : ";

        return ans;
    }
}

namespace subtaskFull{
    bool check(){
        return true;
    }

    ll solve(){
        vector<vector<pair<int, int>>> atColumn(n + 1);
        vector<vector<ll>> pref(n + 1);
        vector<vector<ll>> f(n + 1);
        vector<vector<ll>> g(n + 1);
        vector<int> nFishes(n + 1);

        rep(i, 0, m){
            int x = fishes[i].x + 1, y = fishes[i].y + 1, w = fishes[i].w;
            atColumn[x].push_back({y, w});
        }

        const ll inf = 1e18;
        FOR(i, 1, n){
            atColumn[i].push_back({0, 0});
            atColumn[i].push_back({n + 1, 0});
            sort(all(atColumn[i]));

            for(auto [j, c] : atColumn[i]){
            }

            nFishes[i] = sz(atColumn[i]);
            pref[i].resize(nFishes[i]);
            f[i].resize(nFishes[i], 0);
            g[i].resize(nFishes[i], 0);

            for(int j = 1; j < nFishes[i]; ++j){
                pref[i][j] = pref[i][j - 1] + atColumn[i][j].second;
            }

//            cout << "column : " << i << '\n';
//            for(int j = 0; j < nFishes[i]; ++j){
//                cout << pref[i][j] << ' ';
//            }
//            cout << '\n';
        }

        auto sumPrefix = [&](int col, int row){
            int pos = upper_bound(all(atColumn[col]), make_pair(row + 1, -1)) - atColumn[col].begin() - 1;
            assert(-1 < pos && pos < sz(atColumn[col]));
            return pref[col][pos];
        };

        FOR(c, 2, n){
            long long mx = -inf;
            for(int r = 0, i = 0; r < nFishes[c]; ++r){
                if(r == 0){
                    maximize(f[c][r], g[c - 1][r]);
                }

                while(i < nFishes[c - 1] && atColumn[c - 1][i].first <= atColumn[c][r].first){
                    maximize(mx, f[c - 1][i] - pref[c - 1][i]);
                    ++i;
                }

                assert(i > 0);
                maximize(f[c][r], mx + sumPrefix(c - 1, atColumn[c][r].first));
            }


            if(c > 2){
                mx = -inf;

                //case when max(r, k) = k
                for(int r = nFishes[c] - 1, i = nFishes[c - 2] - 1; r >= 0; --r){
                    while(i > 0 && atColumn[c - 2][i].first >= atColumn[c][i].first){
                        maximize(mx, max(f[c - 2][i], g[c - 2][i]) + sumPrefix(c - 1, atColumn[c - 2][i].first));
                        --i;
                    }

                    maximize(f[c][r], mx);
                }

                //case when max(r, k) = r
                mx = -inf;
                for(int r = 0, i = 1; r < nFishes[c]; ++r){
                    while(i < nFishes[c - 2] && atColumn[c - 2][i].first <= atColumn[c][r].first){
                        maximize(mx, max(f[c - 2][i], g[c - 2][i]) + sumPrefix(c - 1, atColumn[c][r].first));
                        ++i;
                    }

                    maximize(f[c][r], mx);
                }
            }

            mx = -inf;
            for(int r = nFishes[c] - 1, i = nFishes[c - 1] - 1; r >= 0; --r){
                while(i >= 0 && atColumn[c - 1][i].first >= atColumn[c][r].first){
                    maximize(mx, max(f[c - 1][i], g[c - 1][i]) + sumPrefix(c, atColumn[c - 1][i].first));
                    --i;
                }

                g[c][r] = mx - pref[c][r];
            }
        }

        ll ans = 0;
        FOR(c, 1, n){
//            cout << "column : " << dbg(c) << '\n';
            for(int r = 0; r < nFishes[c]; ++r){
//                cout << "f(" << c << ", " << atColumn[c][r].first << ") = " << f[c][r] << '\n';
//                cout << "g(" << c << ", " << atColumn[c][r].first << ") = " << g[c][r] << '\n';
//                cout << dbg(f[c][r]) << ' ';
                maximize(ans, max(f[c][r], g[c][r]) + (c == n ? 0 : sumPrefix(c + 1, atColumn[c][r].first)));
            }
//            cout << '\n';
        }
        return ans;
    }


}

ll max_weights(int N, int M, vector<int> X, vector<int> Y, vector<int> W){
    n = N;
    m = M;
    rep(i, 0, M) fishes[i] = {X[i], Y[i], W[i]};

    if(subtask1::check()) return subtask1::solve();
    if(subtask2::check()) return subtask2::solve();
    if(subtask3::check()) return subtask3::solve();
    if(subtask45::check()) return subtask45::solve();
    if(subtaskFull::check()) return subtaskFull::solve();

    return -1;
}

#ifdef LOCAL
int main(){
    freopen("task.inp", "r", stdin);
    freopen("task.out", "w", stdout);

    int N, M;
    cin >> N >> M;
    vector<int> X(M), Y(M), W(M);
    rep(i, 0, M){
        cin >> X[i] >> Y[i] >> W[i];
    }

    cout << max_weights(N, M, X, Y, W) << '\n';
}
#endif // LOCAL

Compilation message

fish.cpp: In function 'bool minimize(T&, const T&)':
fish.cpp:18:5: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
   18 |     if(a > b) return a = b, true; return false;
      |     ^~
fish.cpp:18:35: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
   18 |     if(a > b) return a = b, true; return false;
      |                                   ^~~~~~
fish.cpp: In function 'bool maximize(T&, const T&)':
fish.cpp:23:5: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
   23 |     if(a < b) return a = b, true; return false;
      |     ^~
fish.cpp:23:35: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
   23 |     if(a < b) return a = b, true; return false;
      |                                   ^~~~~~
fish.cpp: In function 'll subtaskFull::solve()':
fish.cpp:239:22: warning: structured binding declaration set but not used [-Wunused-but-set-variable]
  239 |             for(auto [j, c] : atColumn[i]){
      |                      ^~~~~~

Subtask #1
3.0 / 3.0

# Verdict Execution time Memory Grader output
1 Correct 19 ms 7760 KB Output is correct
2 Correct 20 ms 8528 KB Output is correct
3 Correct 1 ms 2384 KB Output is correct
4 Correct 1 ms 2384 KB Output is correct
5 Correct 67 ms 19048 KB Output is correct
6 Correct 67 ms 19272 KB Output is correct

Subtask #2
6.0 / 6.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 20816 KB Output is correct
2 Correct 36 ms 29532 KB Output is correct
3 Correct 42 ms 31196 KB Output is correct
4 Correct 18 ms 7760 KB Output is correct
5 Correct 22 ms 8528 KB Output is correct
6 Correct 3 ms 20816 KB Output is correct
7 Correct 3 ms 20816 KB Output is correct
8 Correct 3 ms 21120 KB Output is correct
9 Correct 4 ms 20816 KB Output is correct
10 Correct 1 ms 2384 KB Output is correct
11 Correct 1 ms 2384 KB Output is correct
12 Correct 21 ms 26192 KB Output is correct
13 Correct 25 ms 26960 KB Output is correct
14 Correct 32 ms 26188 KB Output is correct
15 Correct 24 ms 26696 KB Output is correct
16 Correct 21 ms 26192 KB Output is correct
17 Correct 29 ms 26440 KB Output is correct

Subtask #3
9.0 / 9.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2384 KB Output is correct
2 Correct 2 ms 6480 KB Output is correct
3 Correct 14 ms 10716 KB Output is correct
4 Correct 11 ms 10064 KB Output is correct
5 Correct 21 ms 12624 KB Output is correct
6 Correct 17 ms 11856 KB Output is correct
7 Correct 19 ms 12500 KB Output is correct
8 Correct 20 ms 12380 KB Output is correct

Subtask #4
14.0 / 14.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2384 KB Output is correct
2 Correct 1 ms 2384 KB Output is correct
3 Correct 3 ms 20816 KB Output is correct
4 Correct 3 ms 20816 KB Output is correct
5 Correct 2 ms 20816 KB Output is correct
6 Correct 3 ms 20944 KB Output is correct
7 Correct 3 ms 21120 KB Output is correct
8 Correct 1 ms 2384 KB Output is correct
9 Correct 9 ms 4944 KB Output is correct
10 Correct 64 ms 6224 KB Output is correct
11 Correct 8 ms 4944 KB Output is correct
12 Correct 53 ms 5968 KB Output is correct
13 Correct 3 ms 4856 KB Output is correct
14 Correct 53 ms 6176 KB Output is correct

Subtask #5
21.0 / 21.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2384 KB Output is correct
2 Correct 1 ms 2384 KB Output is correct
3 Correct 3 ms 20816 KB Output is correct
4 Correct 3 ms 20816 KB Output is correct
5 Correct 2 ms 20816 KB Output is correct
6 Correct 3 ms 20944 KB Output is correct
7 Correct 3 ms 21120 KB Output is correct
8 Correct 1 ms 2384 KB Output is correct
9 Correct 9 ms 4944 KB Output is correct
10 Correct 64 ms 6224 KB Output is correct
11 Correct 8 ms 4944 KB Output is correct
12 Correct 53 ms 5968 KB Output is correct
13 Correct 3 ms 4856 KB Output is correct
14 Correct 53 ms 6176 KB Output is correct
15 Correct 54 ms 5968 KB Output is correct
16 Correct 3 ms 4704 KB Output is correct
17 Correct 65 ms 10040 KB Output is correct
18 Correct 64 ms 9820 KB Output is correct
19 Correct 69 ms 10012 KB Output is correct
20 Correct 65 ms 9808 KB Output is correct
21 Correct 64 ms 9808 KB Output is correct
22 Correct 73 ms 11600 KB Output is correct
23 Correct 58 ms 6480 KB Output is correct
24 Correct 65 ms 9296 KB Output is correct
25 Correct 67 ms 5968 KB Output is correct
26 Correct 58 ms 6480 KB Output is correct

Subtask #6
0 / 17.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2384 KB Output is correct
2 Correct 1 ms 2384 KB Output is correct
3 Correct 3 ms 20816 KB Output is correct
4 Correct 3 ms 20816 KB Output is correct
5 Correct 2 ms 20816 KB Output is correct
6 Correct 3 ms 20944 KB Output is correct
7 Correct 3 ms 21120 KB Output is correct
8 Correct 1 ms 2384 KB Output is correct
9 Correct 9 ms 4944 KB Output is correct
10 Correct 64 ms 6224 KB Output is correct
11 Correct 8 ms 4944 KB Output is correct
12 Correct 53 ms 5968 KB Output is correct
13 Correct 3 ms 4856 KB Output is correct
14 Correct 53 ms 6176 KB Output is correct
15 Correct 54 ms 5968 KB Output is correct
16 Correct 3 ms 4704 KB Output is correct
17 Correct 65 ms 10040 KB Output is correct
18 Correct 64 ms 9820 KB Output is correct
19 Correct 69 ms 10012 KB Output is correct
20 Correct 65 ms 9808 KB Output is correct
21 Correct 64 ms 9808 KB Output is correct
22 Correct 73 ms 11600 KB Output is correct
23 Correct 58 ms 6480 KB Output is correct
24 Correct 65 ms 9296 KB Output is correct
25 Correct 67 ms 5968 KB Output is correct
26 Correct 58 ms 6480 KB Output is correct
27 Incorrect 3 ms 3152 KB 1st lines differ - on the 1st token, expected: '2999', found: '1999'
28 Halted 0 ms 0 KB -

Subtask #7
0 / 14.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2384 KB Output is correct
2 Correct 2 ms 6480 KB Output is correct
3 Correct 14 ms 10716 KB Output is correct
4 Correct 11 ms 10064 KB Output is correct
5 Correct 21 ms 12624 KB Output is correct
6 Correct 17 ms 11856 KB Output is correct
7 Correct 19 ms 12500 KB Output is correct
8 Correct 20 ms 12380 KB Output is correct
9 Incorrect 63 ms 32072 KB 1st lines differ - on the 1st token, expected: '99999', found: '66666'
10 Halted 0 ms 0 KB -

Subtask #8
0 / 16.0

# Verdict Execution time Memory Grader output
1 Correct 19 ms 7760 KB Output is correct
2 Correct 20 ms 8528 KB Output is correct
3 Correct 1 ms 2384 KB Output is correct
4 Correct 1 ms 2384 KB Output is correct
5 Correct 67 ms 19048 KB Output is correct
6 Correct 67 ms 19272 KB Output is correct
7 Correct 3 ms 20816 KB Output is correct
8 Correct 36 ms 29532 KB Output is correct
9 Correct 42 ms 31196 KB Output is correct
10 Correct 18 ms 7760 KB Output is correct
11 Correct 22 ms 8528 KB Output is correct
12 Correct 3 ms 20816 KB Output is correct
13 Correct 3 ms 20816 KB Output is correct
14 Correct 3 ms 21120 KB Output is correct
15 Correct 4 ms 20816 KB Output is correct
16 Correct 1 ms 2384 KB Output is correct
17 Correct 1 ms 2384 KB Output is correct
18 Correct 21 ms 26192 KB Output is correct
19 Correct 25 ms 26960 KB Output is correct
20 Correct 32 ms 26188 KB Output is correct
21 Correct 24 ms 26696 KB Output is correct
22 Correct 21 ms 26192 KB Output is correct
23 Correct 29 ms 26440 KB Output is correct
24 Correct 1 ms 2384 KB Output is correct
25 Correct 2 ms 6480 KB Output is correct
26 Correct 14 ms 10716 KB Output is correct
27 Correct 11 ms 10064 KB Output is correct
28 Correct 21 ms 12624 KB Output is correct
29 Correct 17 ms 11856 KB Output is correct
30 Correct 19 ms 12500 KB Output is correct
31 Correct 20 ms 12380 KB Output is correct
32 Correct 1 ms 2384 KB Output is correct
33 Correct 1 ms 2384 KB Output is correct
34 Correct 3 ms 20816 KB Output is correct
35 Correct 3 ms 20816 KB Output is correct
36 Correct 2 ms 20816 KB Output is correct
37 Correct 3 ms 20944 KB Output is correct
38 Correct 3 ms 21120 KB Output is correct
39 Correct 1 ms 2384 KB Output is correct
40 Correct 9 ms 4944 KB Output is correct
41 Correct 64 ms 6224 KB Output is correct
42 Correct 8 ms 4944 KB Output is correct
43 Correct 53 ms 5968 KB Output is correct
44 Correct 3 ms 4856 KB Output is correct
45 Correct 53 ms 6176 KB Output is correct
46 Correct 54 ms 5968 KB Output is correct
47 Correct 3 ms 4704 KB Output is correct
48 Correct 65 ms 10040 KB Output is correct
49 Correct 64 ms 9820 KB Output is correct
50 Correct 69 ms 10012 KB Output is correct
51 Correct 65 ms 9808 KB Output is correct
52 Correct 64 ms 9808 KB Output is correct
53 Correct 73 ms 11600 KB Output is correct
54 Correct 58 ms 6480 KB Output is correct
55 Correct 65 ms 9296 KB Output is correct
56 Correct 67 ms 5968 KB Output is correct
57 Correct 58 ms 6480 KB Output is correct
58 Incorrect 3 ms 3152 KB 1st lines differ - on the 1st token, expected: '2999', found: '1999'
59 Halted 0 ms 0 KB -