Submission #1074041

#	Time	Username	Problem	Language	Result	Execution time	Memory
1074041		GrindMachine	Naval battle (CEOI24_battle)	C++17	30 / 100	1209 ms	103108 KiB

Main

#include <bits/stdc++.h>
using namespace std;

typedef long long int ll;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;

#define fastio ios_base::sync_with_stdio(false); cin.tie(NULL)
#define pb push_back
#define endl '\n'
#define conts continue
#define sz(a) (int)a.size()
#define ff first
#define ss second
#define all(a) a.begin(),a.end()
#define rall(a) a.rbegin(),a.rend()

#define rep(i,n) for(int i = 0; i < n; ++i)
#define rep1(i,n) for(int i = 1; i <= n; ++i)
#define rev(i,s,e) for(int i = s; i >= e; --i)
#define trav(i,a) for(auto &i : a)

template<typename T>
void amin(T &x, T y){
	x = min(x,y);
}

template<typename T>
void amax(T &x, T y){
	x = max(x,y);
}

template<typename A,typename B>
string to_string(pair<A,B> p);

string to_string(const string &s){
	return "'"+s+"'";
}

string to_string(const char* s){
	return to_string((string)s);
}

string to_string(bool b){
	return b?"true":"false";
}

template<typename A>
string to_string(A v){
	string res = "{";
	trav(x,v){
		res += to_string(x)+",";
	}
	if(res.back() == ',') res.pop_back();
	res += "}";
	return res;
}

template<typename A,typename B>
string to_string(pair<A,B> p){
	return "("+to_string(p.ff)+","+to_string(p.ss)+")";
}

#define debug(x) cout << "[" << #x << "]: "; cout << to_string(x) << endl

const int MOD = 1e9 + 7;
const int N = 1e5 + 5;
const int inf1 = 1e9 + 5;
const ll inf2 = (ll)1e18 + 5;

void solve(int test_case){
	int n; cin >> n;
	vector<array<int,3>> a(n+5);
	rep1(i,n){
		int r,c; cin >> r >> c;
		char ch; cin >> ch;
		swap(r,c);
		int d = -1;
		if(ch == 'E') d = 0;
		if(ch == 'W') d = 1;
		if(ch == 'S') d = 2;
		if(ch == 'N') d = 3;
		a[i] = {r,c,d};
	}

	auto f = [&](int i, int j){
		if(a[i][2] > a[j][2]) swap(i,j);
		auto [ri,ci,di] = a[i];
		auto [rj,cj,dj] = a[j];
		if(di == dj) return 2*inf1;

		int t = 2*inf1;

		if((di^1) == dj){
			if(di == 0){
				if(ri == rj and ci <= cj){
					t = (cj-ci)/2;
				}
			}
			else{
				if(ci == cj and ri <= rj){
					t = (rj-ri)/2;
				}
			}
		}
		else{
			assert(di == 0 or di == 1);
			if(di == 0){
				if(ci <= cj){
					if(dj == 2){
						if(ri-rj == cj-ci){
							t = abs(ri-rj);
						}
					}
					else{
						if(rj-ri == cj-ci){
							t = abs(ri-rj);
						}
					}
				}
			}
			else{
				if(ci >= cj){
					if(dj == 2){
						if(ri-rj == ci-cj){
							t = abs(ri-rj);
						}
					}
					else{
						if(rj-ri == ci-cj){
							t = abs(ri-rj);
						}
					}
				}
			}
		}

		return t;
	};

	map<int,set<pii>> mp[4][2];
	vector<vector<int>> dt = {
		{0,1},
		{2,3},
		{0,2},
		{1,3}
	};

	rep1(i,n){
		auto [r,c,d] = a[i];
		array<int,4> keys = {r,c,r+c,r-c};
		rep(j,4){
			int id = find(all(dt[j]),d)-dt[j].begin();
			if(id <= 1){
				int val = c;
				if(j&1) val = r;
				mp[j][id][keys[j]].insert({val,i});
			}
		}
	}

	priority_queue<array<int,3>,vector<array<int,3>>,greater<array<int,3>>> pq;

	auto nxt_collision = [&](int i, int j) -> array<int,3>{
		auto [r,c,d] = a[i];
		int id = find(all(dt[j]),d)-dt[j].begin();
		if(id >= 2) return {-1,-1,-1};
		int val = c;
		if(j&1) val = r;
		array<int,4> keys = {r,c,r+c,r-c};

		auto &st = mp[j][id^1][keys[j]];
		auto it = st.upper_bound({val,-1});
		int k = -1;

		if(id == 0){
			if(it != st.end()){
				k = it->ss;
			}
		}
		else{
			if(it != st.begin()){
				it--;
				k = it->ss;
			}
		}

		if(k != -1){
			int t = f(i,k);
			if(t < 2*inf1){
				pq.push({t,i,k});
				return {t,i,k};
			}
		}

		return {-1,-1,-1};
	};

	rep1(i,n){
		rep(j,4){
			nxt_collision(i,j);
		}
	}

	vector<int> remt(n+5,2*inf1);
	vector<bool> rem(n+5);
	int pt = -1;

	while(!pq.empty()){
		auto [t,i,j] = pq.top();
		pq.pop();

		if(rem[i] and rem[j]) conts;
		if(min(remt[i],remt[j]) < t){
			rep(x,4){
				if(!rem[i]){
					nxt_collision(i,x);
				}
				if(!rem[j]){
					nxt_collision(j,x);
				}
			}

			conts;
		}

		pt = t;
		remt[i] = remt[j] = t;
		vector<int> del = {i,j};

		trav(i,del){
			if(rem[i]) conts;
			rem[i] = 1;
			auto [r,c,d] = a[i];
			array<int,4> keys = {r,c,r+c,r-c};
			rep(j,4){
				int id = find(all(dt[j]),d)-dt[j].begin();
				if(id <= 1){
					int val = c;
					if(j&1) val = r;
					mp[j][id][keys[j]].erase({val,i});
				}
			}
		}
	}

	vector<int> ans;
	rep1(i,n){
		if(!rem[i]){
			ans.pb(i);
		}
	}

	trav(x,ans) cout << x << endl;

	// while(true){
	// 	mnt = inf1;
	// 	del.clear();

	// 	for(auto &[val,st] : mpr){
	// 		ll prev_occ[4];
	// 		memset(prev_occ,-1,sizeof prev_occ);
	// 		for(auto [v1,i] : st){
	// 			rep(d,4){
	// 				int j = prev_occ[d];
	// 				if(j != -1){
	// 					upd(i,j);
	// 				}
	// 			}
	// 			prev_occ[a[i][2]] = i;
	// 		}
	// 	}

	// 	for(auto &[val,st] : mpc){
	// 		ll prev_occ[4];
	// 		memset(prev_occ,-1,sizeof prev_occ);
	// 		for(auto [v1,i] : st){
	// 			rep(d,4){
	// 				int j = prev_occ[d];
	// 				if(j != -1){
	// 					upd(i,j);
	// 				}
	// 			}
	// 			prev_occ[a[i][2]] = i;
	// 		}
	// 	}

	// 	for(auto &[val,st] : mpsum){
	// 		ll prev_occ[4];
	// 		memset(prev_occ,-1,sizeof prev_occ);
	// 		for(auto [v1,i] : st){
	// 			rep(d,4){
	// 				int j = prev_occ[d];
	// 				if(j != -1){
	// 					upd(i,j);
	// 				}
	// 			}
	// 			prev_occ[a[i][2]] = i;
	// 		}
	// 	}

	// 	for(auto &[val,st] : mpdiff){
	// 		ll prev_occ[4];
	// 		memset(prev_occ,-1,sizeof prev_occ);
	// 		for(auto [v1,i] : st){
	// 			rep(d,4){
	// 				int j = prev_occ[d];
	// 				if(j != -1){
	// 					upd(i,j);
	// 				}
	// 			}
	// 			prev_occ[a[i][2]] = i;
	// 		}
	// 	}

	// 	if(mnt == inf1) break;

	// 	trav(i,del){
	// 		rem[i] = 1;
	// 		auto [r,c,d] = a[i];
	// 		mpr[r].erase({c,i});
	// 		mpc[c].erase({r,i});
	// 		mpsum[r+c].erase({c,i});
	// 		mpdiff[r-c].erase({c,i});
	// 	}
	// }

	// vector<int> ans;
	// rep1(i,n){
	// 	if(!rem[i]){
	// 		ans.pb(i);
	// 	}
	// }

	// trav(x,ans) cout << x << endl;
}

int main(){
	fastio;

	int t = 1;
	// cin >> t;

	rep1(i,t){
		solve(i);
	}

	return 0;
}

Compilation message (stderr)

Main.cpp: In function 'void solve(int)':
Main.cpp:207:6: warning: variable 'pt' set but not used [-Wunused-but-set-variable]
  207 |  int pt = -1;
      |      ^~

• Subtask 0: 0 / 0
• Subtask 1: 0 / 6
• Subtask 2: 0 / 12
• Subtask 3: 0 / 8
• Subtask 4: 0 / 11
• Subtask 5: 0 / 9
• Subtask 6: 30 / 30
• Subtask 7: 0 / 24