Submission #914736

# Submission time Handle Problem Language Result Execution time Memory
914736 2024-01-22T15:42:36 Z qin Furniture (JOI20_furniture) C++17
100 / 100
311 ms 21076 KB
#include <bits/stdc++.h>
#define fi first
#define se second
#define ssize(x) int(x.size())
#define pn printf("\n");
#define all(x) x.begin(),x.end()
#define rall(x) x.rbegin(),x.rend()
#define vv vector
using namespace std;
typedef long long ll;
typedef pair<int, int> pii;
int inf = 2e09; ll infll = 2e18; int mod = 119<<23|1;
void bfs_up(vv<vv<int>> &t, vv<vv<int>> &ed, pii st, vv<set<int>> &s){
		queue<pii> q;
		if(!t[st.fi-1][st.se]) q.emplace(pii(st.fi-1, st.se));
		if(!t[st.fi][st.se-1]) q.emplace(pii(st.fi, st.se-1));
		while(!q.empty()){
				int i = q.front().fi, j = q.front().se; q.pop();
				//~ printf("%d %d\n", i, j);
				if(!t[i+1][j] || !t[i][j+1] || t[i][j]) continue; // nie musimy usuwać, bo jest przejście
				t[i][j] = 1;
				
				auto it = prev(s[i].upper_bound(j)); // modyfikuję seta, nie sądzę, że muszę sprawdzać czy begin
				if(*it == j) s[i].erase(it);
				else ed[i][*it] = j-1;
				
				if(!t[i-1][j]) q.emplace(pii(i-1, j));
				if(!t[i][j-1]) q.emplace(pii(i, j-1));
		}
}
void bfs_down(vv<vv<int>> &t, vv<vv<int>> &ed, pii st, vv<set<int>> &s){
		queue<pii> q;
		if(!t[st.fi+1][st.se]) q.emplace(pii(st.fi+1, st.se));
		if(!t[st.fi][st.se+1]) q.emplace(pii(st.fi, st.se+1));
		while(!q.empty()){
				int i = q.front().fi, j = q.front().se; q.pop();
				//~ printf("%d %d\n", i, j);
				if(!t[i-1][j] || !t[i][j-1] || t[i][j]) continue; // nie musimy usuwać, bo jest przejście
				t[i][j] = 1;
				
				auto it = s[i].lower_bound(j); // modyfikuję seta
				assert(it != s[i].end());
				if(ed[i][*it] == j) s[i].erase(it);
				else{ int tmp = *it; ed[i][*it+1] = ed[i][*it], ed[i][*it] = 0, s[i].erase(it), s[i].emplace(tmp+1); }
				
				if(!t[i+1][j]) q.emplace(pii(i+1, j));
				if(!t[i][j+1]) q.emplace(pii(i, j+1));
		}
}
void answer(){
		int n, m; scanf("%d%d", &n, &m);
		vv<vv<int>> t(n+2, vv<int>(m+2, 0)), ed(n+2, vv<int>(m+2, 0)); // w e trzymam koniec przedziału, ktory jest na secie
		vector<pii> red;
		for(int i = 1; i <= n; ++i){
				for(int j = 1, a; j <= m; ++j){ scanf("%d", &a);  if(a) red.emplace_back(i, j); }
		}
		for(int i = 0; i <= n+1; ++i) t[i][0] = 1, t[i][m+1] = 1; // narożników chyba nie muszę, ale kto wie, zostawiam komentarz
		for(int j = 1; j <= m; ++j) t[0][j] = 1, t[n+1][j] = 1;
		vv<set<int>> s(n+2);
		for(int i = 1; i <= n; ++i) s[i].emplace(1), ed[i][1] = m;
		
		for(pii &u : red){
				int i = u.fi, j = u.se;
				//~ if((i == 1 && j == 1) || (i == n && j == m)) continue;
				if(t[i][j]) continue;
				auto it = prev(s[i].upper_bound(j));
				if(ed[i][*it] != j) ed[i][j+1] = ed[i][*it], s[i].emplace(j+1);
				it = prev(s[i].upper_bound(j));
				if(*it != j) ed[i][*it] = j-1;
				else s[i].erase(it); 
				t[i][j] = 1;
				//~ printf("a\n");
				bfs_up(t, ed, pii(i, j), s);
				bfs_down(t, ed, pii(i, j), s);
				//~ pn;
				//~ for(i = 1; i <= n; ++i){
						//~ for(j = 1; j <= m; ++j) printf("%d ", t[i][j]);
						//~ pn;
				//~ }
				//~ for(i = 1; i <= n; ++i){
						//~ for(int x : s[i]) printf("%d %d, ", x, ed[i][x]);
						//~ pn;
				//~ }
		}
		int q; scanf("%d", &q);
		for(++q; --q; ){
				int i, j; scanf("%d%d", &i, &j);
				if(t[i][j]){ printf("1\n"); continue; }
				if(ssize(s[i]) > 1){
						printf("1\n");
						auto it = prev(s[i].upper_bound(j));
						if(ed[i][*it] != j) ed[i][j+1] = ed[i][*it], s[i].emplace(j+1);
						it = prev(s[i].upper_bound(j));
						if(*it != j) ed[i][*it] = j-1;
						else s[i].erase(it); 
						t[i][j] = 1;
						bfs_up(t, ed, pii(i, j), s), bfs_down(t, ed, pii(i, j), s);
						continue;
				}
				
				bool left = 1, right = 1;
				auto it = prev(s[i].upper_bound(j));
				int it_beg = *it, it_ed = ed[i][*it];
				if(*it == j) left = 0;
				if(it_ed == j) right = 0;
				if(right){
						bool good = 0;
						it = s[i-1].lower_bound(j+1);
						if(it != s[i-1].end() && *it <= it_ed) good = 1;
						if(it != s[i-1].begin() && j+1 <= ed[i-1][*prev(it)]) good = 1;
						if(!good) right = 0;
				}
				if(left){
						bool good = 0;
						it = s[i+1].lower_bound(it_beg);
						if(it != s[i+1].end() && *it <= j-1) good = 1;
						if(it != s[i+1].begin() && it_beg <= ed[i+1][*prev(it)]) good = 1;
						if(!good) left = 0;
				}
				if(!left && !right) printf("0\n");
				else{
						printf("1\n");
						it = prev(s[i].upper_bound(j));
						if(ed[i][*it] != j) ed[i][j+1] = ed[i][*it], s[i].emplace(j+1);
						it = prev(s[i].upper_bound(j));
						if(*it != j) ed[i][*it] = j-1;
						else s[i].erase(it); 
						t[i][j] = 1;
						bfs_up(t, ed, pii(i, j), s), bfs_down(t, ed, pii(i, j), s);
				}
		}
}
int main(){
		int T = 1;
		for(++T; --T; ) answer();
		return 0;
}

Compilation message

furniture.cpp: In function 'void answer()':
furniture.cpp:51:18: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   51 |   int n, m; scanf("%d%d", &n, &m);
      |             ~~~~~^~~~~~~~~~~~~~~~
furniture.cpp:55:42: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   55 |     for(int j = 1, a; j <= m; ++j){ scanf("%d", &a);  if(a) red.emplace_back(i, j); }
      |                                     ~~~~~^~~~~~~~~~
furniture.cpp:85:15: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   85 |   int q; scanf("%d", &q);
      |          ~~~~~^~~~~~~~~~
furniture.cpp:87:20: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   87 |     int i, j; scanf("%d%d", &i, &j);
      |               ~~~~~^~~~~~~~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 1 ms 348 KB Output is correct
2 Correct 1 ms 348 KB Output is correct
3 Correct 2 ms 604 KB Output is correct
4 Correct 3 ms 604 KB Output is correct
5 Correct 3 ms 600 KB Output is correct
6 Correct 4 ms 600 KB Output is correct
7 Correct 3 ms 604 KB Output is correct
8 Correct 3 ms 564 KB Output is correct
9 Correct 3 ms 604 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 348 KB Output is correct
2 Correct 1 ms 348 KB Output is correct
3 Correct 2 ms 604 KB Output is correct
4 Correct 3 ms 604 KB Output is correct
5 Correct 3 ms 600 KB Output is correct
6 Correct 4 ms 600 KB Output is correct
7 Correct 3 ms 604 KB Output is correct
8 Correct 3 ms 564 KB Output is correct
9 Correct 3 ms 604 KB Output is correct
10 Correct 10 ms 1368 KB Output is correct
11 Correct 3 ms 604 KB Output is correct
12 Correct 274 ms 16456 KB Output is correct
13 Correct 94 ms 13260 KB Output is correct
14 Correct 300 ms 20652 KB Output is correct
15 Correct 311 ms 20304 KB Output is correct
16 Correct 235 ms 18264 KB Output is correct
17 Correct 238 ms 19312 KB Output is correct
18 Correct 301 ms 21076 KB Output is correct
19 Correct 271 ms 20044 KB Output is correct
20 Correct 234 ms 19928 KB Output is correct
21 Correct 258 ms 20164 KB Output is correct