Submission #679996

#	Time	Username	Problem	Language	Result	Execution time	Memory
679996		bashkort	Wombats (IOI13_wombats)	C++17	76 / 100	20055 ms	40116 KiB

wombats

#include <bits/stdc++.h>
#include "wombats.h"

using namespace std;

inline bool ckmin(int &a, int b) {
    return (a > b) && (a = b, true);
}

constexpr int B = 70, R = 5000, C = 200, K = (R + B - 1) / B;

int r, c, need;
int dp[K][C][C], fr[K][C][C], H[R][C], V[R][C];

void update_dp(int L) {
    if (L == need - 1) {
        memcpy(dp[L], fr[L], sizeof(dp[L]));
        return;
    }
    memset(dp[L], 0x3f, sizeof(dp[L]));
    for (int cc = 0; cc < c; ++cc) {
        const int idx = (L + 1) * B - 1;
        
        function<void(int, int, int, int)> solve = [&](int l, int r, int optl, int optr) {
            if (l >= r) {
                return;
            }

            int mid = (l + r) >> 1;

            int opt = optl;

            for (int b = optl; b <= optr; ++b) {
                if (ckmin(dp[L][mid][cc], fr[L][mid][b] + V[idx][b] + dp[L + 1][b][cc])) {
                    opt = b;
                }
            }

            solve(l, mid, optl, opt), solve(mid + 1, r, opt, optr);
        };
        solve(0, c, 0, c - 1);
    }

}

void update_fr(int L) {
    memset(fr[L], 0x3f, sizeof(fr[L]));
    for (int a = 0; a < c; ++a) {
        fr[L][a][a] = 0;
    }
    int lim = B * L;
    for (int i = min(r, B * (L + 1)) - 1; i >= lim; --i) {
        for (int a = 0; a < c - 1; ++a) {
            for (int cc = 0; cc < c; ++cc)
                ckmin(fr[L][a + 1][cc], fr[L][a][cc] + H[i][a]);
        }
        for (int a = c - 2; a >= 0; --a) {
            for (int cc = 0; cc < c; ++cc)
                ckmin(fr[L][a][cc], fr[L][a + 1][cc] + H[i][a]);
        }
        if (i != lim) {
            for (int cc = 0; cc < c; ++cc) {
                for (int a = 0; a < c; ++a) {
                    fr[L][a][cc] += V[i - 1][a];
                }
            }
        }
    }
}

void init(int R, int C, int H[5000][200], int V[5000][200]) {
    r = R, c = C;
    memcpy(::H, H, sizeof(::H)), memcpy(::V, V, sizeof(::V));

    need = (r + B - 1) / B;
    for (int i = need - 1; i >= 0; --i) {
        update_fr(i);
    }
    for (int i = need - 1; i >= 0; --i) {
        update_dp(i);
    }
}

void changeH(int P, int Q, int W) {
    H[P][Q] = W;

    int L = P / B;

    update_fr(L);

    if (L == need - 1) {
        memcpy(dp[L], fr[L], sizeof(dp[L]));
    } else {
        update_dp(L);
    }
    for (int i = L - 1; i >= 0; --i) {
        update_dp(i);
    }
}

void changeV(int P, int Q, int W) {
    V[P][Q] = W;

    int L = P / B;

    if ((P + 1) % B != 0) {
        update_fr(L);
    }
    for (int i = L; i >= 0; --i) {
        update_dp(i);
    }
}

int escape(int V1, int V2) {
    return dp[0][V1][V2];
}

Compilation message (stderr)

grader.c: In function 'int main()':
grader.c:15:6: warning: variable 'res' set but not used [-Wunused-but-set-variable]
   15 |  int res;
      |      ^~~

• Subtask 1: 9 / 9
• Subtask 2: 12 / 12
• Subtask 3: 16 / 16
• Subtask 4: 18 / 18
• Subtask 5: 21 / 21
• Subtask 6: 0 / 24