#pragma GCC optimize("Ofast")
#pragma GCC target("avx,avx2,fma")
#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define all(x) x.begin(), x.end()
typedef pair<int, int> II;
template<typename T> bool maximize(T& a, T b) {return (a < b ? a = b, 1 : 0);}
template<typename T> bool minimize(T& a, T b) {return (a > b ? a = b, 1 : 0);}
const int N = 2e3 + 1;
const int dx[] = {-1, 0, 1, 0};
const int dy[] = {0, 1, 0, -1};
int n, m;
int xs, ys, xe, ye, d[N][N];
char a[N][N];
bool checkDir(const int &num, const char &dir)
{
if(dir == '.') return 1;
if(num == 0 && dir == '^') return 0;
if(num == 1 && dir == '>') return 0;
if(num == 2 && dir == 'v') return 0;
if(num == 3 && dir == '<') return 0;
return 1;
}
II trace[N][N];
void BFS()
{
queue<II> Q;
Q.push({xs, ys});
d[xs][ys] = 0;
while(Q.size())
{
auto cur = Q.front();
Q.pop();
for(int i = 0; i < 4; i++)
{
const int &X = cur.first + dx[i];
const int &Y = cur.second + dy[i];
if(X < 1 || X > n || Y < 1 || Y > m) continue;
if(minimize(d[X][Y], d[cur.first][cur.second] + checkDir(i, a[cur.first][cur.second])))
{
trace[X][Y] = {cur.first, cur.second};
Q.push({X, Y});
}
}
}
}
void Trace()
{
II cur = {xe, ye};
while(cur.first != xs || cur.second != ys)
{
II new_cur = trace[cur.first][cur.second];
const int &X = new_cur.first;
const int &Y = new_cur.second;
if(cur.first > X) a[X][Y] = 'v';
else if(cur.first < X) a[X][Y] = '^';
else if(cur.second < Y) a[X][Y] = '<';
else a[X][Y] = '>';
cur = new_cur;
}
}
signed main()
{
ios_base::sync_with_stdio(false);
cin.tie(NULL);
memset(d, 0x3f, sizeof(d));
cin >> n >> m;
for(int i = 1; i <= n; i++)
for(int j = 1; j <= m; j++)
{
cin >> a[i][j];
if(a[i][j] == 'o') xs = i, ys = j;
else if (a[i][j] == 'x') xe = i, ye = j;
}
BFS();
Trace();
cout << d[xe][ye] - 1 << '\n';
a[xs][ys] = 'o';
for(int i = 1; i <= n; i++)
{
for(int j = 1; j <= m; j++) cout << a[i][j];
cout << '\n';
}
return 0;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
7 ms |
15956 KB |
Output is correct |
2 |
Correct |
7 ms |
15996 KB |
Output is correct |
3 |
Correct |
9 ms |
15996 KB |
Output is correct |
4 |
Correct |
6 ms |
16000 KB |
Output is correct |
5 |
Correct |
6 ms |
15992 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
7 ms |
15956 KB |
Output is correct |
2 |
Correct |
7 ms |
15996 KB |
Output is correct |
3 |
Correct |
9 ms |
15996 KB |
Output is correct |
4 |
Correct |
6 ms |
16000 KB |
Output is correct |
5 |
Correct |
6 ms |
15992 KB |
Output is correct |
6 |
Correct |
494 ms |
24632 KB |
Output is correct |
7 |
Correct |
268 ms |
26492 KB |
Output is correct |
8 |
Correct |
1991 ms |
35416 KB |
Output is correct |
9 |
Correct |
1188 ms |
45436 KB |
Output is correct |
10 |
Execution timed out |
2059 ms |
41812 KB |
Time limit exceeded |
11 |
Halted |
0 ms |
0 KB |
- |