답안 #625685

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
625685 2022-08-10T16:59:45 Z Clan328 메기 농장 (IOI22_fish) C++17
53 / 100
1000 ms 353216 KB
#include "bits/stdc++.h"
using namespace std;
 
#define int long long
struct Fish {
    int col, row;
    int weight;
};
bool operator < (const Fish& a, const Fish& b) {
    if (a.col != b.col) return a.col < b.col;
    return a.row < b.row;
}
 
// sub1 - 3 {{{
// fishes are on even columns -> build piers on odd columns
// & catch all fishes
int sub1(const std::vector<Fish>& fishes) {
    int res = 0;
    for (const auto& fish : fishes) {
        res += fish.weight;
    }
    return res;
}
 
// fishes are on first 2 columns
int sub2(int n, const std::vector<Fish>& fishes) {
    std::vector<int> zeroes(n);  // prefix sum of fish weights at column == 0
    std::vector<int> ones(n);    // prefix sum of fish weights at column == 1
    for (const auto& fish : fishes) {
        if (fish.col == 0) zeroes[fish.row] += fish.weight;
        if (fish.col == 1) ones[fish.row] += fish.weight;
    }
 
    std::partial_sum(zeroes.begin(), zeroes.end(), zeroes.begin());
    std::partial_sum(ones.begin(), ones.end(), ones.begin());
 
    int res = ones.back();  // init: only catch fishes at column == 1
    for (int i = 0; i < n; ++i) {
        // build pier until at column 1, row 0-i
        if (n == 2) res = std::max(res, zeroes[i]);
        else res = std::max(res, zeroes[i] + ones.back() - ones[i]);
    }
    return res;
}
 
// all fishes are on row == 0
int sub3(int n, const std::vector<Fish>& fishes) {
    std::vector<int> weights(n);  // weights[i] = weight of fish at column i
    for (const auto& fish : fishes) {
        weights[fish.col] += fish.weight;
    }
 
    // f[i] = best strategy if we BUILD PIER AT i, only considering col 0..i
    // i-4 i-3 i-2 i-1 i
    std::vector<int> f(n);
    f[0] = 0;
    for (int i = 1; i < n; ++i) {
        f[i] = std::max(f[i-1], weights[i-1]);
        if (i >= 2) {
            f[i] = std::max(f[i], f[i-2] + weights[i-1]);
        }
        if (i >= 3) {
            f[i] = std::max(f[i], f[i-3] + weights[i-2] + weights[i-1]);
        }
    }
 
    int res = 0;
    for (int i = 0; i < n; ++i) {
        int cur = f[i];
        if (i + 1 < n) cur += weights[i+1];
        res = std::max(res, cur);
    }
    return res;
}
// }}}
 
// N <= 300
int sub5(int n, const std::vector<Fish>& fishes) {
    // Init weights[i][j] = sum of fish on column i, from row 0 -> row j
    std::vector<std::vector<int>> weights(n, std::vector<int> (n, 0));
    for (const auto& fish : fishes) {
        weights[fish.col][fish.row] += fish.weight;
    }
    for (int col = 0; col < n; ++col) {
        std::partial_sum(weights[col].begin(), weights[col].end(), weights[col].begin());
    }
 
    // f[c][r] = best strategy if we last BUILD PIER AT column c, row r
    //           only considering fishes <= (c, r)
    // g[c][r] = similar to f[c][r] but consider fishes at column c, in row [r, n-1]
    std::vector<std::vector<int>> f(n, std::vector<int> (n, 0)),
                                  g(n, std::vector<int> (n, 0));
    // f <= g
    for (int c = 1; c < n; ++c) {
        for (int r = 0; r < n; ++r) {
            // this is first pier
            f[c][r] = g[c][r] = weights[c-1][r];
 
            // last pier at column i-1
            for (int lastRow = 0; lastRow < n; ++lastRow) {
                if (lastRow <= r) {
                    int cur = std::max(
                            f[c-1][lastRow] + weights[c-1][r] - weights[c-1][lastRow],
                            g[c-1][lastRow]);
                    f[c][r] = std::max(f[c][r], cur);
                    g[c][r] = std::max(g[c][r], cur);
                } else {
                    f[c][r] = std::max(f[c][r], g[c-1][lastRow]);
                    g[c][r] = std::max(
                            g[c][r],
                            g[c-1][lastRow] + weights[c][lastRow] - weights[c][r]);
                }
            }
 
            // last pier at column i-2
            if (c >= 2) {
                for (int lastRow = 0; lastRow < n; ++lastRow) {
                    int cur = g[c-2][lastRow] + weights[c-1][std::max(lastRow, r)];
                    f[c][r] = std::max(f[c][r], cur);
                    g[c][r] = std::max(g[c][r], cur);
                }
            }
           
        }
    }
 
    int res = 0;
    for (int c = 0; c < n; ++c) {
        for (int r = 0; r < n; ++r) {
            assert(g[c][r] >= f[c][r]);
            int cur = g[c][r];
            if (c + 1 < n) {
                cur += weights[c+1][r];
            }
            res = std::max(res, cur);
        }
    }
    return res;
}
 
// N <= 3000
int sub6(int n, const std::vector<Fish>& fishes) {
    // Init weights[i][j] = sum of fish on column i, from row 0 -> row j
    std::vector<std::vector<int>> weights(n, std::vector<int> (n, 0));
    for (const auto& fish : fishes) {
        weights[fish.col][fish.row] += fish.weight;
    }
    for (int col = 0; col < n; ++col) {
        std::partial_sum(weights[col].begin(), weights[col].end(), weights[col].begin());
    }
 
    // f[c][r] = best strategy if we last BUILD PIER AT column c, row r
    //           only considering fishes <= (c, r)
    // g[c][r] = similar to f[c][r] but consider fishes at column c, in row [r, n-1]
    std::vector<std::vector<int>> f(n, std::vector<int> (n, 0)),
                                  g(n, std::vector<int> (n, 0)),
                                  g_agg(n, std::vector<int> (n, 0)),
                                  g_agg_with_next_col(n, std::vector<int> (n, 0));
 
    // f <= g
    for (int c = 0; c < n; ++c) {
        // compute {{{
        if (c > 0) {
            for (int r = 0; r < n; ++r) {
                // this is first pier
                f[c][r] = g[c][r] = weights[c-1][r];
 
                // last pier at column i-1
                for (int lastRow = 0; lastRow < n; ++lastRow) {
                    if (lastRow <= r) {
                        int cur = std::max(
                                f[c-1][lastRow] + weights[c-1][r] - weights[c-1][lastRow],
                                g[c-1][lastRow]);
                        f[c][r] = std::max(f[c][r], cur);
                        g[c][r] = std::max(g[c][r], cur);
                    } else {
                        f[c][r] = std::max(f[c][r], g[c-1][lastRow]);
                        g[c][r] = std::max(
                                g[c][r],
                                g[c-1][lastRow] + weights[c][lastRow] - weights[c][r]);
                    }
                }
 
                // last pier at column i-2
                if (c >= 2) {
                    int cur = std::max(
                            g_agg[c-2].back() + weights[c-1][r],
                            g_agg_with_next_col[c-2].back());
                    f[c][r] = std::max(f[c][r], cur);
                    g[c][r] = std::max(g[c][r], cur);
                }
                
                // last pier at column i-3
                if (c >= 3) {
                    int cur = g_agg_with_next_col[c-3].back() + weights[c-1][r];
                    f[c][r] = std::max(f[c][r], cur);
                    g[c][r] = std::max(g[c][r], cur);
                }
            }
        }
        // }}}
        
        // aggregate {{{
        // g_agg[c][r] = max(g[c][0], .., g[c][r])
        std::partial_sum(g[c].begin(), g[c].end(), g_agg[c].begin(),
                [] (auto a, auto b) { return std::max(a, b); });
 
        if (c + 1 < n) {
            // g_agg_with_next_col[c][r] = max(
            //     g[c][0] + weights[c+1][0],
            //     ...
            //     g[c][r] + weights[c+1][r])
            g_agg_with_next_col[c][0] = g[c][0] + weights[c+1][0];
            for (int r = 1; r < n; ++r) {
                g_agg_with_next_col[c][r] = std::max(
                        g_agg_with_next_col[c][r-1],
                        g[c][r] + weights[c+1][r]);
            }
        }
        // }}}
    }
 
    int res = 0;
    for (int c = 0; c < n; ++c) {
        for (int r = 0; r < n; ++r) {
            assert(g[c][r] >= f[c][r]);
            int cur = g[c][r];
            if (c + 1 < n) {
                cur += weights[c+1][r];
            }
            res = std::max(res, cur);
        }
    }
    return res;
 
}
 
#undef int
long long max_weights(
        int n, int nFish,
        std::vector<int> xs,
        std::vector<int> ys,
        std::vector<int> ws) {
    std::vector<Fish> fishes;
    for (int i = 0; i < nFish; ++i) {
        fishes.push_back({xs[i], ys[i], ws[i]});
    }
 
    if (std::all_of(xs.begin(), xs.end(), [] (int x) { return x % 2 == 0; })) {
        return sub1(fishes);
    }
    if (*std::max_element(xs.begin(), xs.end()) <= 1) {
        return sub2(n, fishes);
    }
    if (*std::max_element(ys.begin(), ys.end()) == 0) {
        return sub3(n, fishes);
    }
    if (n <= 3000) {
        return sub6(n, fishes);
    }
    return 0;
}
# 결과 실행 시간 메모리 Grader output
1 Correct 27 ms 5340 KB Output is correct
2 Correct 29 ms 5832 KB Output is correct
3 Correct 1 ms 212 KB Output is correct
4 Correct 0 ms 212 KB Output is correct
5 Correct 95 ms 19788 KB Output is correct
6 Correct 110 ms 19788 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 54 ms 10396 KB Output is correct
3 Correct 64 ms 11200 KB Output is correct
4 Correct 24 ms 5344 KB Output is correct
5 Correct 30 ms 5828 KB Output is correct
6 Correct 0 ms 212 KB Output is correct
7 Correct 0 ms 212 KB Output is correct
8 Correct 1 ms 212 KB Output is correct
9 Correct 0 ms 212 KB Output is correct
10 Correct 0 ms 212 KB Output is correct
11 Correct 0 ms 212 KB Output is correct
12 Correct 26 ms 5448 KB Output is correct
13 Correct 30 ms 6464 KB Output is correct
14 Correct 25 ms 5472 KB Output is correct
15 Correct 29 ms 6088 KB Output is correct
16 Correct 26 ms 5448 KB Output is correct
17 Correct 28 ms 6072 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 1 ms 1876 KB Output is correct
3 Correct 16 ms 4132 KB Output is correct
4 Correct 12 ms 3672 KB Output is correct
5 Correct 30 ms 6444 KB Output is correct
6 Correct 24 ms 6464 KB Output is correct
7 Correct 30 ms 6460 KB Output is correct
8 Correct 30 ms 6448 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 0 ms 212 KB Output is correct
4 Correct 0 ms 212 KB Output is correct
5 Correct 1 ms 212 KB Output is correct
6 Correct 0 ms 212 KB Output is correct
7 Correct 0 ms 212 KB Output is correct
8 Correct 0 ms 212 KB Output is correct
9 Correct 12 ms 1108 KB Output is correct
10 Correct 93 ms 3996 KB Output is correct
11 Correct 12 ms 1236 KB Output is correct
12 Correct 93 ms 3932 KB Output is correct
13 Correct 2 ms 468 KB Output is correct
14 Correct 93 ms 3924 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 0 ms 212 KB Output is correct
4 Correct 0 ms 212 KB Output is correct
5 Correct 1 ms 212 KB Output is correct
6 Correct 0 ms 212 KB Output is correct
7 Correct 0 ms 212 KB Output is correct
8 Correct 0 ms 212 KB Output is correct
9 Correct 12 ms 1108 KB Output is correct
10 Correct 93 ms 3996 KB Output is correct
11 Correct 12 ms 1236 KB Output is correct
12 Correct 93 ms 3932 KB Output is correct
13 Correct 2 ms 468 KB Output is correct
14 Correct 93 ms 3924 KB Output is correct
15 Correct 91 ms 3880 KB Output is correct
16 Correct 2 ms 596 KB Output is correct
17 Correct 116 ms 5976 KB Output is correct
18 Correct 102 ms 5996 KB Output is correct
19 Correct 103 ms 5952 KB Output is correct
20 Correct 106 ms 5960 KB Output is correct
21 Correct 103 ms 6084 KB Output is correct
22 Correct 115 ms 8124 KB Output is correct
23 Correct 95 ms 4304 KB Output is correct
24 Correct 101 ms 5196 KB Output is correct
25 Correct 91 ms 3924 KB Output is correct
26 Correct 95 ms 4272 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 0 ms 212 KB Output is correct
4 Correct 0 ms 212 KB Output is correct
5 Correct 1 ms 212 KB Output is correct
6 Correct 0 ms 212 KB Output is correct
7 Correct 0 ms 212 KB Output is correct
8 Correct 0 ms 212 KB Output is correct
9 Correct 12 ms 1108 KB Output is correct
10 Correct 93 ms 3996 KB Output is correct
11 Correct 12 ms 1236 KB Output is correct
12 Correct 93 ms 3932 KB Output is correct
13 Correct 2 ms 468 KB Output is correct
14 Correct 93 ms 3924 KB Output is correct
15 Correct 91 ms 3880 KB Output is correct
16 Correct 2 ms 596 KB Output is correct
17 Correct 116 ms 5976 KB Output is correct
18 Correct 102 ms 5996 KB Output is correct
19 Correct 103 ms 5952 KB Output is correct
20 Correct 106 ms 5960 KB Output is correct
21 Correct 103 ms 6084 KB Output is correct
22 Correct 115 ms 8124 KB Output is correct
23 Correct 95 ms 4304 KB Output is correct
24 Correct 101 ms 5196 KB Output is correct
25 Correct 91 ms 3924 KB Output is correct
26 Correct 95 ms 4272 KB Output is correct
27 Execution timed out 1105 ms 353216 KB Time limit exceeded
28 Halted 0 ms 0 KB -
# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 1 ms 1876 KB Output is correct
3 Correct 16 ms 4132 KB Output is correct
4 Correct 12 ms 3672 KB Output is correct
5 Correct 30 ms 6444 KB Output is correct
6 Correct 24 ms 6464 KB Output is correct
7 Correct 30 ms 6460 KB Output is correct
8 Correct 30 ms 6448 KB Output is correct
9 Incorrect 25 ms 5824 KB 1st lines differ - on the 1st token, expected: '99999', found: '0'
10 Halted 0 ms 0 KB -
# 결과 실행 시간 메모리 Grader output
1 Correct 27 ms 5340 KB Output is correct
2 Correct 29 ms 5832 KB Output is correct
3 Correct 1 ms 212 KB Output is correct
4 Correct 0 ms 212 KB Output is correct
5 Correct 95 ms 19788 KB Output is correct
6 Correct 110 ms 19788 KB Output is correct
7 Correct 0 ms 212 KB Output is correct
8 Correct 54 ms 10396 KB Output is correct
9 Correct 64 ms 11200 KB Output is correct
10 Correct 24 ms 5344 KB Output is correct
11 Correct 30 ms 5828 KB Output is correct
12 Correct 0 ms 212 KB Output is correct
13 Correct 0 ms 212 KB Output is correct
14 Correct 1 ms 212 KB Output is correct
15 Correct 0 ms 212 KB Output is correct
16 Correct 0 ms 212 KB Output is correct
17 Correct 0 ms 212 KB Output is correct
18 Correct 26 ms 5448 KB Output is correct
19 Correct 30 ms 6464 KB Output is correct
20 Correct 25 ms 5472 KB Output is correct
21 Correct 29 ms 6088 KB Output is correct
22 Correct 26 ms 5448 KB Output is correct
23 Correct 28 ms 6072 KB Output is correct
24 Correct 0 ms 212 KB Output is correct
25 Correct 1 ms 1876 KB Output is correct
26 Correct 16 ms 4132 KB Output is correct
27 Correct 12 ms 3672 KB Output is correct
28 Correct 30 ms 6444 KB Output is correct
29 Correct 24 ms 6464 KB Output is correct
30 Correct 30 ms 6460 KB Output is correct
31 Correct 30 ms 6448 KB Output is correct
32 Correct 0 ms 212 KB Output is correct
33 Correct 0 ms 212 KB Output is correct
34 Correct 0 ms 212 KB Output is correct
35 Correct 0 ms 212 KB Output is correct
36 Correct 1 ms 212 KB Output is correct
37 Correct 0 ms 212 KB Output is correct
38 Correct 0 ms 212 KB Output is correct
39 Correct 0 ms 212 KB Output is correct
40 Correct 12 ms 1108 KB Output is correct
41 Correct 93 ms 3996 KB Output is correct
42 Correct 12 ms 1236 KB Output is correct
43 Correct 93 ms 3932 KB Output is correct
44 Correct 2 ms 468 KB Output is correct
45 Correct 93 ms 3924 KB Output is correct
46 Correct 91 ms 3880 KB Output is correct
47 Correct 2 ms 596 KB Output is correct
48 Correct 116 ms 5976 KB Output is correct
49 Correct 102 ms 5996 KB Output is correct
50 Correct 103 ms 5952 KB Output is correct
51 Correct 106 ms 5960 KB Output is correct
52 Correct 103 ms 6084 KB Output is correct
53 Correct 115 ms 8124 KB Output is correct
54 Correct 95 ms 4304 KB Output is correct
55 Correct 101 ms 5196 KB Output is correct
56 Correct 91 ms 3924 KB Output is correct
57 Correct 95 ms 4272 KB Output is correct
58 Execution timed out 1105 ms 353216 KB Time limit exceeded
59 Halted 0 ms 0 KB -