Submission #943199

# Submission time Handle Problem Language Result Execution time Memory
943199 2024-03-11T09:13:39 Z kxd Portals (BOI14_portals) C++17
100 / 100
322 ms 100932 KB
#include <bits/stdc++.h>
//#define DEBUG 1106
#define int long long
#define ll long long
#define ld long double
#define pb push_back
#define p_q priority_queue
#define m_p make_pair
#define pii pair<int,int>
#define endl '\n'
#define INIT ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
#define FOR(i,a,b) for(int i = a; i <= b; i++)
#define forn(i,n) for (int i = 0; i < n; i++)
#define forn1(i,n) for (int i = 1; i <= n; i++)
#define all(x) x.begin(),x.end()
#define ft first
#define sd second
#define lowbit(x) (x&(-x))
#define chmax(x,y) x=max(x,y)
#define chmin(x,y) x=min(x,y)
#ifdef DEBUG
#define debug(x) cout << #x << ": " << x << endl;
#else
#define debug(x) 1106;
#endif

using namespace std;
const int N = 1106;
const int inf = 1e9;
const int INF = 1e18;
const int MOD = 1e9+7;

const int dx[4] = {1,-1,0,0};
const int dy[4] = {0,0,1,-1};

int dist[N][N], wall[N][N];
char a[N][N];
pii p[N][N][4];

signed main() {
	INIT
	#ifdef DEBUG
	freopen("input.txt", "r", stdin);
	#endif
	///////////
	forn(i,1005) {
		forn(j,1005) {
			wall[i][j] = (int)1e9;
		}
	}
	forn(i,1005) {
		forn(j,1005) {
			dist[i][j] = (int)1e9;
		}
	}
	int n, m;
	cin >> n >> m;
	n += 2, m += 2;
	forn(i,n) {
		forn(j,m) {
			if (i == 0 || j == 0 || j == m - 1 || i == n - 1) a[i][j] = '#';
			else cin >> a[i][j];
		}
	}
	int sx, sy, ex, ey;
	queue<pii> Q;	
	forn(i,n) {
		forn(j,m) {
			if (a[i][j] == 'S') sx = i, sy = j;
			if (a[i][j] == 'C') ex = i, ey = j;
			if (a[i][j]== '#') {
				wall[i][j] = 0;
				Q.push({i,j});
			}
		}
	}
	while(!Q.empty()){
		auto [x,y] = Q.front();
		Q.pop();
		for (int dir = 0; dir < 4; dir++){
			int nx = x + dx[dir];
			int ny = y + dy[dir];
			if (nx < n && nx >= 0 && ny < m && ny >= 0){
				if (wall[nx][ny] > wall[x][y] + 1){
					Q.push({nx,ny});
					wall[nx][ny] = wall[x][y] + 1;
				}
			}
		}
	}
	forn(j,m) {
		int t = 0;
		forn(i,n) {
			if (a[i][j] == '#') {
				t = i;
			}
			p[i][j][0] = {t + 1,j};
		}
		t = n - 1;
		for (int i = n - 1; i>=0; i--){
			if (a[i][j] == '#'){
				t = i;
			}
			p[i][j][1] = {t - 1,j};
		}
	}
	forn(i,n) {
		int t = 0;
		forn(j,m){
			if (a[i][j] == '#'){
				t = j;
			}
			p[i][j][3] = {i, t + 1};
		}
		t = m - 1;
		for (int j = m - 1; j>=0; j--){
			if (a[i][j] == '#'){
				t = j;
			}
			p[i][j][2] = {i,t - 1};
		}
	}
	p_q<pair<int,pii>> pq;
	pq.push({0,{sx,sy}});
	dist[sx][sy]=0;
	while(!pq.empty()){
		int d = -pq.top().ft;
		auto [x,y] = pq.top().sd;
		pq.pop();
		if (d != dist[x][y]) continue;
		for (int dir = 0; dir < 4; dir++){
			int nx = x + dx[dir];
			int ny = y + dy[dir];
			if (nx < n && nx >= 0 && ny < m && ny >= 0){
				if (a[nx][ny] != '#'){
					if (dist[nx][ny] > d + 1){
						pq.push({-d-1, {nx,ny}});
						dist[nx][ny] = d + 1;
					}
				}
			}
			nx = p[x][y][dir].ft;
			ny = p[x][y][dir].sd;
			if (dist[nx][ny] > wall[x][y] + d){
				if (a[nx][ny] != '#'){
					dist[nx][ny] = d + wall[x][y];
					pq.push({-dist[nx][ny], {nx,ny}});
				}
			}
		}
	}
	cout << dist[ex][ey];
}

Compilation message

portals.cpp: In function 'int main()':
portals.cpp:125:14: warning: 'sy' may be used uninitialized in this function [-Wmaybe-uninitialized]
  125 |  dist[sx][sy]=0;
      |  ~~~~~~~~~~~~^~
portals.cpp:152:21: warning: 'ey' may be used uninitialized in this function [-Wmaybe-uninitialized]
  152 |  cout << dist[ex][ey];
      |                     ^
portals.cpp:152:21: warning: 'ex' may be used uninitialized in this function [-Wmaybe-uninitialized]
portals.cpp:125:14: warning: 'sx' may be used uninitialized in this function [-Wmaybe-uninitialized]
  125 |  dist[sx][sy]=0;
      |  ~~~~~~~~~~~~^~
# Verdict Execution time Memory Grader output
1 Correct 4 ms 20824 KB Output is correct
2 Correct 4 ms 23020 KB Output is correct
3 Correct 4 ms 22876 KB Output is correct
4 Correct 4 ms 22876 KB Output is correct
5 Correct 4 ms 22876 KB Output is correct
6 Correct 5 ms 22876 KB Output is correct
7 Correct 4 ms 22876 KB Output is correct
8 Correct 5 ms 23128 KB Output is correct
9 Correct 4 ms 22876 KB Output is correct
10 Correct 5 ms 22876 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 3 ms 20824 KB Output is correct
2 Correct 4 ms 22992 KB Output is correct
3 Correct 4 ms 22872 KB Output is correct
4 Correct 4 ms 22876 KB Output is correct
5 Correct 4 ms 22876 KB Output is correct
6 Correct 4 ms 22876 KB Output is correct
7 Correct 4 ms 22876 KB Output is correct
8 Correct 4 ms 22876 KB Output is correct
9 Correct 5 ms 25332 KB Output is correct
10 Correct 4 ms 24924 KB Output is correct
11 Correct 4 ms 25048 KB Output is correct
12 Correct 4 ms 24924 KB Output is correct
13 Correct 4 ms 25044 KB Output is correct
14 Correct 4 ms 22876 KB Output is correct
15 Correct 4 ms 24924 KB Output is correct
16 Correct 4 ms 22876 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 3 ms 20828 KB Output is correct
2 Correct 3 ms 22876 KB Output is correct
3 Correct 4 ms 22876 KB Output is correct
4 Correct 4 ms 22876 KB Output is correct
5 Correct 9 ms 35676 KB Output is correct
6 Correct 10 ms 35588 KB Output is correct
7 Correct 10 ms 35676 KB Output is correct
8 Correct 9 ms 35932 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 3 ms 20828 KB Output is correct
2 Correct 4 ms 22876 KB Output is correct
3 Correct 4 ms 22876 KB Output is correct
4 Correct 5 ms 22876 KB Output is correct
5 Correct 5 ms 22872 KB Output is correct
6 Correct 4 ms 22876 KB Output is correct
7 Correct 4 ms 23044 KB Output is correct
8 Correct 4 ms 22872 KB Output is correct
9 Correct 4 ms 24924 KB Output is correct
10 Correct 5 ms 24924 KB Output is correct
11 Correct 4 ms 24924 KB Output is correct
12 Correct 4 ms 24924 KB Output is correct
13 Correct 6 ms 24924 KB Output is correct
14 Correct 9 ms 35672 KB Output is correct
15 Correct 10 ms 35676 KB Output is correct
16 Correct 12 ms 35676 KB Output is correct
17 Correct 10 ms 35676 KB Output is correct
18 Correct 11 ms 35676 KB Output is correct
19 Correct 13 ms 35420 KB Output is correct
20 Correct 12 ms 35420 KB Output is correct
21 Correct 9 ms 35676 KB Output is correct
22 Correct 10 ms 35588 KB Output is correct
23 Correct 11 ms 35804 KB Output is correct
24 Correct 11 ms 35468 KB Output is correct
25 Correct 4 ms 22876 KB Output is correct
26 Correct 4 ms 24924 KB Output is correct
27 Correct 4 ms 23032 KB Output is correct
28 Correct 8 ms 35672 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 5 ms 20828 KB Output is correct
2 Correct 4 ms 22876 KB Output is correct
3 Correct 5 ms 22876 KB Output is correct
4 Correct 5 ms 22876 KB Output is correct
5 Correct 4 ms 22876 KB Output is correct
6 Correct 4 ms 22876 KB Output is correct
7 Correct 4 ms 22876 KB Output is correct
8 Correct 4 ms 22876 KB Output is correct
9 Correct 5 ms 25060 KB Output is correct
10 Correct 4 ms 24924 KB Output is correct
11 Correct 4 ms 25068 KB Output is correct
12 Correct 4 ms 24924 KB Output is correct
13 Correct 5 ms 24924 KB Output is correct
14 Correct 9 ms 35932 KB Output is correct
15 Correct 10 ms 35844 KB Output is correct
16 Correct 10 ms 35676 KB Output is correct
17 Correct 10 ms 35676 KB Output is correct
18 Correct 12 ms 35676 KB Output is correct
19 Correct 12 ms 35364 KB Output is correct
20 Correct 12 ms 35416 KB Output is correct
21 Correct 9 ms 35676 KB Output is correct
22 Correct 10 ms 35676 KB Output is correct
23 Correct 10 ms 35844 KB Output is correct
24 Correct 200 ms 96572 KB Output is correct
25 Correct 322 ms 91936 KB Output is correct
26 Correct 275 ms 91704 KB Output is correct
27 Correct 256 ms 91516 KB Output is correct
28 Correct 141 ms 98428 KB Output is correct
29 Correct 164 ms 100932 KB Output is correct
30 Correct 195 ms 97972 KB Output is correct
31 Correct 11 ms 35456 KB Output is correct
32 Correct 243 ms 91240 KB Output is correct
33 Correct 4 ms 22876 KB Output is correct
34 Correct 4 ms 25076 KB Output is correct
35 Correct 214 ms 95316 KB Output is correct
36 Correct 4 ms 22872 KB Output is correct
37 Correct 8 ms 35676 KB Output is correct
38 Correct 123 ms 96868 KB Output is correct
39 Correct 161 ms 99572 KB Output is correct