#include <iostream>
#include <vector>
#include <queue>
using namespace std;
typedef pair <int, int> PII;
const int NMAX = 502, INF = 1e9;
const int dx[4] = {-1, 0, 1, 0};
const int dy[4] = {0, 1, 0, -1};
char v[NMAX][NMAX];
int d[NMAX * NMAX], sel[NMAX * NMAX];
int N, M;
vector < PII > G[NMAX * NMAX];
auto cmp = [](PII a, PII b)
{
if(!(a.first < b.first))
return 1;
return 0;
};
priority_queue <PII, vector <PII>, decltype(cmp)> H(cmp);
inline int code(PII a)
{
if(!(1 <= a.first && a.first <= N && 1 <= a.second && a.second <= M))
return 0;
if(v[a.first][a.second] == 'X' && (a.first != N || a.second != M))
return 0;
return (a.first - 1) * M + a.second;
}
inline PII decode(int x)
{
if(x % M == 0)
return {x / M, M};
return {x / M, x % M};
}
inline void Read()
{
cin.tie(nullptr);
ios_base::sync_with_stdio(false);
cin >> N >> M;
for(int i = 1; i <= N; ++i)
{
cin >> (v[i] + 1);
for(int j = 1; j <= M; ++j)
{
if(v[i][j] == 'X' && (i != N || j != M))
continue;
PII est = {i, j + 1}, west = {i, j - 1}, sud = {i + 1, j}, nord = {i - 1, j};
int ct = code({i, j});
if(v[i][j] == 'E')
{
G[ct].push_back({0, code (est)});
G[ct].push_back({1, code (sud)});
G[ct].push_back({2, code (west)});
G[ct].push_back({3, code (nord)});
}
if(v[i][j] == 'S')
{
G[ct].push_back({0, code (sud)});
G[ct].push_back({1, code (west)});
G[ct].push_back({2, code (nord)});
G[ct].push_back({3, code (est)});
}
if(v[i][j] == 'W')
{
G[ct].push_back({0, code (west)});
G[ct].push_back({1, code (nord)});
G[ct].push_back({2, code (est)});
G[ct].push_back({3, code (sud)});
}
if(v[i][j] == 'N')
{
G[ct].push_back({0, code (nord)});
G[ct].push_back({1, code (est)});
G[ct].push_back({2, code (sud)});
G[ct].push_back({3, code (west)});
}
}
}
return;
}
inline void Dijkstra(int start)
{
for(int i = 1; i <= code({N, M}); ++i)
d[i] = INF;
for(auto it: G[start])
if(it.second)
H.push(it), d[it.second] = it.first;
d[start] = 0;
sel[start] = 1;
while(!H.empty())
{
while(!H.empty() && sel[H.top().second])
H.pop();
if(H.empty())
return;
int node = H.top().second;
sel[node] = 1;
H.pop();
for(auto it: G[node])
if(it.second)
if(d[node] + it.first < d[it.second])
d[it.second] = d[node] + it.first, H.push({d[it.second], it.second});
}
return;
}
int main()
{
Read();
Dijkstra(1);
cout << d[code({N, M})] << '\n';
return 0;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
4 ms |
6220 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
4 ms |
6220 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
3 ms |
6240 KB |
Output is correct |
2 |
Correct |
3 ms |
6220 KB |
Output is correct |
3 |
Incorrect |
3 ms |
6220 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
4 ms |
6220 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
4 ms |
6220 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |