#include <bits/stdc++.h>
using namespace std;
template<typename T>
void out(T x) { cout << x << endl; exit(0); }
#define watch(x) cout << (#x) << " is " << (x) << endl
using ll = long long;
const int maxn = 1010;
const int inf = 1e9;
int n, m;
string g[maxn];
int dp[maxn][maxn];
int dr[4]={0,0,1,-1};
int dc[4]={1,-1,0,0};
int L[maxn][maxn], R[maxn][maxn], U[maxn][maxn], D[maxn][maxn];
int main() {
ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
cin>>n>>m;
g[0] = string(m+2, '#');
g[n+1] = string(m+2, '#');
for (int i=1; i<=n; i++) {
cin>>g[i];
g[i]="#"+g[i]+"#";
}
for (int i=0; i<=n+1; i++) {
for (int j=0; j<=m+1; j++) {
if (g[i][j]=='#') {
L[i][j]=j;
U[i][j]=i;
} else {
L[i][j]=L[i][j-1];
U[i][j]=U[i-1][j];
}
}
for (int j=m+1; j>=0; j--) {
if (g[i][j]=='#') {
R[i][j]=j;
} else {
R[i][j]=R[i][j+1];
}
}
}
for (int i=n+1; i>=0; i--) {
for (int j=0; j<=m+1; j++) {
if (g[i][j]=='#') {
D[i][j]=i;
} else {
D[i][j]=D[i+1][j];
}
}
}
priority_queue<pair<int,pair<int,int>>> pq;
for (int i=1; i<=n; i++) {
for (int j=1; j<=m; j++) {
dp[i][j] = inf;
if (g[i][j]=='S') {
dp[i][j] = 0;
pq.push({-0, {i,j}});
}
}
}
while (pq.size()) {
auto cur = pq.top();
pq.pop();
int x = cur.second.first;
int y = cur.second.second;
if (-cur.first > dp[x][y]) {
continue;
}
for (int j=0; j<4; j++) {
int nx=x+dr[j];
int ny=y+dc[j];
if (g[nx][ny]=='#') {
int tx=-1,ty=-1;
if (nx==x+1 && ny==y) {
//down
tx=U[x][y]+1; ty=y;
} else if (nx==x-1 && ny==y) {
//up
tx=D[x][y]-1; ty=y;
} else if (nx==x && ny==y+1) {
//right
tx=x; ty=L[x][y]+1;
} else if (nx==x && ny==y-1) {
//left
tx=x; ty=R[x][y]-1;
} else assert(false);
if (dp[tx][ty] > 1+dp[x][y]) {
dp[tx][ty]=1+dp[x][y];
pq.push({-dp[tx][ty],{tx,ty}});
}
} else {
if (dp[nx][ny] > 1+dp[x][y]) {
dp[nx][ny]=1+dp[x][y];
pq.push({-dp[nx][ny],{nx,ny}});
}
}
}
}
for (int i=1; i<=n; i++) {
for (int j=1; j<=m; j++) {
if (g[i][j]=='C') {
out(dp[i][j]);
}
}
}
return 0;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
492 KB |
Output is correct |
2 |
Correct |
1 ms |
620 KB |
Output is correct |
3 |
Correct |
1 ms |
620 KB |
Output is correct |
4 |
Correct |
1 ms |
492 KB |
Output is correct |
5 |
Incorrect |
1 ms |
620 KB |
Output isn't correct |
6 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
492 KB |
Output is correct |
2 |
Correct |
1 ms |
620 KB |
Output is correct |
3 |
Correct |
1 ms |
620 KB |
Output is correct |
4 |
Correct |
1 ms |
492 KB |
Output is correct |
5 |
Incorrect |
1 ms |
620 KB |
Output isn't correct |
6 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
492 KB |
Output is correct |
2 |
Correct |
1 ms |
620 KB |
Output is correct |
3 |
Correct |
1 ms |
620 KB |
Output is correct |
4 |
Incorrect |
1 ms |
620 KB |
Output isn't correct |
5 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
492 KB |
Output is correct |
2 |
Correct |
1 ms |
620 KB |
Output is correct |
3 |
Correct |
1 ms |
620 KB |
Output is correct |
4 |
Correct |
1 ms |
492 KB |
Output is correct |
5 |
Incorrect |
1 ms |
620 KB |
Output isn't correct |
6 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
492 KB |
Output is correct |
2 |
Correct |
1 ms |
620 KB |
Output is correct |
3 |
Correct |
1 ms |
620 KB |
Output is correct |
4 |
Correct |
1 ms |
500 KB |
Output is correct |
5 |
Incorrect |
1 ms |
620 KB |
Output isn't correct |
6 |
Halted |
0 ms |
0 KB |
- |