| # | Time | Username | Problem | Language | Result | Execution time | Memory |
|---|---|---|---|---|---|---|---|
| 250143 | Kevin_Zhang_TW | Cop and Robber (BOI14_coprobber) | 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 "coprobber.h"
#include <bits/stdc++.h>
#define pb emplace_back
using namespace std;
#define MAX_N 500
const int inf = 1e9;
// modify the following functions
// you can define global variables and functions
int dp[MAX_N][MAX_N];
int now, n;
vector<int> edge[MAX_N];
bool con[MAX_N][MAX_N];
bool dfs(int tar, int now, int lst) {
if (now == tar) return true;
for (int u : edge[now]) if (u != lst && dfs(tar, u, now))
return true;
return false;
}
int start(int n, bool A[MAX_N][MAX_N]) {
int m = 0;
for (int i = 0;i < n;++i) {
for (int j = 0;j < n;++j) {
con[i][j] = A[i][j];
if (A[i][j])
edge[i].pb(j), dp[i][j] = 1, ++m;
else
dp[i][j] = inf;
}
dp[i][i] = 0;
}
assert(m == (n-1) * 2);
// for (int i = 0;i < n;++i)
// for (int j = 0;j < n;++j) if (i != j)
// assert(A[i][j]);
for (int a:{1,1,1})
for (int k = 0;k < n;++k)
for (int i = 0;i < n;++i)
for (int j = 0;j < n;++j)
dp[i][j] = min(dp[i][j], dp[i][k] + dp[k][j]);
return now = 0;
// int res = 0;
// for (int i = 0;i < n;++i)
// if (dp[i][i] <= n)
// res = max(res, dp[i][i]), cerr << dp[i][i] << '\n';
// if (res > 4) return -1;
//
// return 0;
}
int nextMove(int R) {
if (now == R)
return R;
assert(dp[i][R] <= n);
// for (int i = 0;i < n;++i)
// if (con[i][now] && dp[i][R] == dp[now][R]-1)
// return now = i;
// return -1;
// for (int i= 0 ;i < n;++i)
// if (con[now][i]) {
// dis = min(dis, dp[i][R]);
// if (dis == dp[i][R])
// go = i;
// }
// return now = go;
for (int u : edge[now])
if (dfs(R, u, now)) {
assert(dp[u][R] == dp[now][R]-1);
return now = u;
}
return -1;
}