Submission #405744

#	Time	Username	Problem	Language	Result	Execution time	Memory
405744		ly20	Stations (IOI20_stations)	C++17	100 / 100	1067 ms	968 KiB

stations

#include "stations.h"
#include <bits/stdc++.h>
using namespace std;
const int MAXN = 1123;
int t, ent[MAXN], sd[MAXN], prof[MAXN];
vector <int> grafo[MAXN];
void dfs(int v, int p) {
    ent[v] = t;
    t++;
    for(int i = 0; i < grafo[v].size(); i++) {
        int viz = grafo[v][i];
        if(viz == p) continue;
        prof[viz] = prof[v] + 1;
        dfs(viz, v);
    }
    sd[v] = t;
    t++;
}
vector<int> label(int n, int k, vector<int> u, vector<int> v) {
	vector<int> labels;
	for(int i =0 ; i < n; i++) grafo[i].clear();
    for(int i = 0; i < u.size(); i++) {
        grafo[u[i]].push_back(v[i]);
        grafo[v[i]].push_back(u[i]);
    }
    prof[0] = 0;
    t = 0;
    dfs(0, 0);
    set <pair <int, int> > s;
    map <pair <int, int>, int> mp;
	for (int i = 0; i < n; i++) {
		if(prof[i] % 2 == 0) s.insert(make_pair(ent[i], 0));
		else s.insert(make_pair(sd[i], 1));
	}
	int at = 0;
	set <pair <int, int> > :: iterator it;
	for(it = s.begin(); it != s.end(); it++) {
        mp[*it] = at++;
	}
    for(int i  = 0; i < n; i++) {
        pair <int, int> a;
        if(prof[i] % 2 == 0) a = make_pair(ent[i], 0);
        else a = make_pair(sd[i], 1);
        labels.push_back(mp[a]);
    }
	return labels;
}

int find_next_station(int s, int t, vector<int> c) {
	int tp, rs, mn = 1123, mx = 0;
	if(c.size() == 1) return c[0];
	for(int i = 0; i < c.size(); i++) {
        int viz = c[i];
        mn = min(viz, mn);
        mx = max(viz, mx);
        if(viz < s) tp = 1;
        if(viz > s) tp = 0;
	}
	vector <int> temp;
	if(tp == 0) {
        rs = mx;
        temp.push_back(s);
        for(int i = 0; i < c.size(); i++) {
            if(c[i] == mx) {
                mx = -mx;
                continue;
            }
            temp.push_back(c[i]);
        }
        sort(temp.begin(), temp.end());
        for(int i = 1; i < temp.size(); i++) {
            if(t >= temp[i - 1] + 1 && t <= temp[i]) {
                return temp[i];
            }
        }
	}
	else {
        rs = mn;
        temp.push_back(s);
        for(int i = 0; i < c.size(); i++) {
            if(c[i] == mn) {
                mn = -mn;
                continue;
            }
            temp.push_back(c[i]);
        }
        sort(temp.begin(), temp.end());
        for(int i = 0; i < temp.size() - 1; i++) {
            if(t >= temp[i] && t <= temp[i + 1] - 1) {
                return temp[i];
            }
        }
	}
    return rs;
}

Compilation message (stderr)

stations.cpp: In function 'void dfs(int, int)':
stations.cpp:10:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   10 |     for(int i = 0; i < grafo[v].size(); i++) {
      |                    ~~^~~~~~~~~~~~~~~~~
stations.cpp: In function 'std::vector<int> label(int, int, std::vector<int>, std::vector<int>)':
stations.cpp:22:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   22 |     for(int i = 0; i < u.size(); i++) {
      |                    ~~^~~~~~~~~~
stations.cpp: In function 'int find_next_station(int, int, std::vector<int>)':
stations.cpp:52:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   52 |  for(int i = 0; i < c.size(); i++) {
      |                 ~~^~~~~~~~~~
stations.cpp:63:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   63 |         for(int i = 0; i < c.size(); i++) {
      |                        ~~^~~~~~~~~~
stations.cpp:71:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   71 |         for(int i = 1; i < temp.size(); i++) {
      |                        ~~^~~~~~~~~~~~~
stations.cpp:80:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   80 |         for(int i = 0; i < c.size(); i++) {
      |                        ~~^~~~~~~~~~
stations.cpp:88:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   88 |         for(int i = 0; i < temp.size() - 1; i++) {
      |                        ~~^~~~~~~~~~~~~~~~~
stations.cpp:60:2: warning: 'tp' may be used uninitialized in this function [-Wmaybe-uninitialized]
   60 |  if(tp == 0) {
      |  ^~

• Subtask 1: 5 / 5
• Subtask 2: 8 / 8
• Subtask 3: 16 / 16
• Subtask 4: 10 / 10
• Subtask 5: 61 / 61