Submission #837963

#	Time	Username	Problem	Language	Result	Execution time	Memory
837963		boyliguanhan	Cop and Robber (BOI14_coprobber)	C++17	100 / 100	267 ms	6604 KiB

coprobber

#include "coprobber.h"
#include<vector>
#define NN 500
#pragma GCC optimize(2)
int ok[NN][NN][2], nxt[NN][NN], vis[NN][NN][2], sz[NN][NN];
bool a[NN][NN];
std::vector<int> adj[NN];
int pos;
void dfs(int x, int y, int who)
{
    ok[x][y][who] = 1;
    if (who == 1) {
        for (auto i : adj[x])
            if (!ok[i][y][0])
                nxt[i][y] = x,dfs(i, y, 0);
        if (!ok[x][y][0])
            nxt[x][y] = x,dfs(x, y, 0);
    } else
        for (auto i : adj[y])
            if (!--sz[x][i] && !ok[x][i][1])
                dfs(x, i, 1);
}
int start(int N, bool A[NN][NN])
{
    for (int i = 0; i < N; i++)
        for (int j = 0; j < N; j++)
            if (A[i][j])
                adj[i].push_back(j);
    for (int i = 0; i < N; i++)
        for (int j = 0; j < N; j++)
            sz[i][j] = adj[j].size();
    for (int i = 0; i < N; i++) {
        if (!ok[i][i][0])
            dfs(i, i , 0);
        if (!ok[i][i][1])
            dfs(i, i, 1);
    }
    for (pos = 0; pos < N; pos++) {
        bool still = 1;
        for (int i = 0; i < N; i++)
            if (!ok[pos][i][0])
                still = 0;
        if (still)
            return pos;
    }
    return -1;
}
int nextMove(int R) {
    return pos=nxt[pos][R];
}

• Subtask 1: 16 / 16
• Subtask 2: 14 / 14
• Subtask 3: 30 / 30
• Subtask 4: 40 / 40