Submission #740223

#	Time	Username	Problem	Language	Result	Execution time	Memory
740223		vjudge1	Fountain Parks (IOI21_parks)	C++17	5 / 100	190 ms	40380 KiB

parks

#include "parks.h"
#include<bits/stdc++.h>
#define f first
#define s second
using namespace std;
const int maxn = 2e5 + 100;
int ord[maxn];
int used[maxn];
int sum;
vector<int>g[maxn];

void dfs(int v){
	used[v] = 1;
	sum++;
	for(auto to: g[v]){
		if(!used[to]) dfs(to);
	}
}

int construct_roads(std::vector<int> x, std::vector<int> y){
    int n = x.size();
	if (x.size() == 1) {
	build({}, {}, {}, {});
        return 1;
    }
	vector<pair<int, int>>c[2];
	for(int i=0; i<n; i++){
		int num = 0;
		if(x[i] == 4) num = 1; 
    	c[num].push_back({y[i], i});
	}
	sort(c[0].begin(), c[0].end());
	sort(c[1].begin(), c[1].end());
	bool ok = 1;
	vector<int>u, v, a, b;
	if(c[1].size() == 0){
		for(int i=1; i<n; i++){
			if(c[0][i].first-c[0][i-1].first != 2) ok = 0;
			u.push_back(c[0][i-1].second);
			v.push_back(c[0][i].second);
			a.push_back(1);
			b.push_back(c[0][i].first-1);
		}
	} else{
		for(int i=1; i<c[0].size(); i++){
			u.push_back(c[0][i-1].second);
			v.push_back(c[0][i].second);
			a.push_back(1);
			b.push_back(c[0][i].first-1);
			g[c[0][i].s].push_back(c[0][i-1].s);
			g[c[0][i-1].s].push_back(c[0][i].s);
		}
		for(int i=1; i<c[1].size(); i++){
			u.push_back(c[1][i-1].second);
			v.push_back(c[1][i].second);
			a.push_back(5);
			b.push_back(c[1][i].first-1);
			g[c[1][i].s].push_back(c[1][i-1].s);
			g[c[1][i-1].s].push_back(c[1][i].s);
		}
		int pos = 0;
		for(int i=0; i<c[0].size(); i++){
			while(pos < c[1].size() && c[1][pos].f < c[0][i].f) pos++;
			if(pos < c[1].size() && c[1][pos].f == c[0][i].f){
				u.push_back(c[0][i].s);
				v.push_back(c[1][pos].s);
				a.push_back(3);
				b.push_back(c[0][i].f-1);
				g[c[0][i].s].push_back(c[1][pos].s);
				g[c[1][pos].s].push_back(c[0][i].s);
			}
		}
		dfs(0);
		if(sum < n) ok = 0;
	}
	if(ok) build(u, v, a, b);
    return ok;
}

Compilation message (stderr)

parks.cpp: In function 'int construct_roads(std::vector<int>, std::vector<int>)':
parks.cpp:45:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   45 |   for(int i=1; i<c[0].size(); i++){
      |                ~^~~~~~~~~~~~
parks.cpp:53:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   53 |   for(int i=1; i<c[1].size(); i++){
      |                ~^~~~~~~~~~~~
parks.cpp:62:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   62 |   for(int i=0; i<c[0].size(); i++){
      |                ~^~~~~~~~~~~~
parks.cpp:63:14: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   63 |    while(pos < c[1].size() && c[1][pos].f < c[0][i].f) pos++;
      |          ~~~~^~~~~~~~~~~~~
parks.cpp:64:11: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   64 |    if(pos < c[1].size() && c[1][pos].f == c[0][i].f){
      |       ~~~~^~~~~~~~~~~~~

• Subtask 1: 5 / 5
• Subtask 2: 0 / 10
• Subtask 3: 0 / 15
• Subtask 4: 0 / 20
• Subtask 5: 0 / 20
• Subtask 6: 0 / 30