Submission #1134308

#	Time	Username	Problem	Language	Result	Execution time	Memory
1134308		amunduzbaev	Naval battle (CEOI24_battle)	C++20	46 / 100	349 ms	123248 KiB

Main

#include "bits/stdc++.h"

using namespace std;

//~ #define int ll
typedef long long ll;
#define ar array

template<class T> bool umin(T& a, T b) { if(b < a) { a = b; return true; } return false; }
template<class T> bool umax(T& a, T b) { if(a < b) { a = b; return true; } return false; }

//~ const int mod = 1e9 + 7;
//~ void add(int& a, const int b){
	//~ a += b;
	//~ while(a >= mod) a -= mod;
	//~ while(a < 0) a += mod;
//~ }

const int inf = 1e9 + 5;

void solve(){
	int n; cin >> n;
	
	vector<int> x(n), y(n), d(n);
	
	vector<ar<int, 2>> coll[3] = {
		{ {0, 3}, {1, 2} },
		{ {2, 3}, {1, 0} },
		{ {1, 3}, {2, 0} }
	};
	
	for(int i=0;i<n;i++){
		char c;
		cin >> x[i] >> y[i] >> c;
		
		if(c == 'N') d[i] = 0;
		if(c == 'E') d[i] = 1;
		if(c == 'S') d[i] = 2;
		if(c == 'W') d[i] = 3;
	}
	
	auto check = [&](int i, int j){
		if(x[i] > x[j]) swap(i, j);
		if(x[i] == x[j] && y[i] > y[j]) swap(i, j);
		ar<int, 2> d_ = {d[i], d[j]};
		
		if(x[i] + y[i] == x[j] + y[j] && (d_ == coll[0][0] || d_ == coll[0][1])){
			return abs(x[i] - x[j]);
		}
		if(x[i] - y[i] == x[j] - y[j] && (d_ == coll[1][0] || d_ == coll[1][1])) {
			return abs(x[i] - x[j]);
		}
		if(d_ == coll[2][0] && y[i] == y[j]) return (x[j] - x[i]) / 2;
		if(d_ == coll[2][1] && x[i] == x[j]) return (y[j] - y[i]) / 2;
		
		return inf + 1;
	};
	
	if(n <= 5000){
		vector<vector<int>> t(n, vector<int>(n, inf));
		vector<ar<int, 3>> colt;
		
		for(int i=0;i<n;i++){
			for(int j=i+1;j<n;j++){
				t[i][j] = check(i, j);
				
				if(t[i][j] <= inf) colt.push_back({t[i][j], i, j});
			}
		}
		
		sort(colt.begin(), colt.end());
		vector<int> liv(n, 1);
		for(int i=0;i<(int)colt.size();){
			int j = i;
			while(j < (int)colt.size() && colt[j][0] == colt[i][0]) j++;
			
			vector<int> dead;
			for(int k=i;k<j;k++){
				auto [time_, x, y] = colt[k];
				
				if(liv[x] && liv[y]){
					dead.push_back(x);
					dead.push_back(y);
				}
			}
			
			for(auto x : dead){
				liv[x] = 0;
			}
			
			i = j;
		}
		
		for(int i=0;i<n;i++){
			if(liv[i]) cout<<i + 1<<"\n";
		}
	} else {
		map<int, vector<int>> diag;
		for(int i=0;i<n;i++){
			diag[x[i] - y[i]].push_back(i);
		}
		
		vector<int> ans;
		for(auto [dg, v] : diag){
			sort(v.begin(), v.end(), [&](int i, int j){
				return x[i] < x[j];
			});
			
			
			vector<int> ss;
			for(auto i : v){
				if(d[i] == 2) ss.push_back(i);
				else {
					if(!ss.empty()) ss.pop_back();
					else ans.push_back(i);
				}
			}
			
			ans.insert(ans.end(), ss.begin(), ss.end());
		}
		
		for(auto x : ans) cout<<++x<<"\n";
		//~ cout<<"\n";
	}
}

signed main(){
	ios_base::sync_with_stdio(0); cin.tie(0);
	
	int t = 1;
	
	//~ cin >> t;
	while(t--){
		solve();
	}
}

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