Submission #293177

#	Time	Username	Problem	Language	Result	Execution time	Memory
293177		egekabas	Highway Tolls (IOI18_highway)	C++14	100 / 100	306 ms	14808 KiB

highway

#include "highway.h"
#include <bits/stdc++.h>
#define all(x) (x).begin(), (x).end()
#define ff first
#define ss second
#define pb push_back
#define mp make_pair
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
typedef pair<ll, ll> pll;
typedef pair<ull, ull> pull;
typedef pair<ll, ll> pii;
typedef pair<ld, ld> pld;
vector<int> w;
vector<pii> g[100000];
int vis[100000];
vector<int> vec[2];
vector<int> u, v;
ll begval;
int col[100000];
int get(vector<int> &vec){
    int l = 0, r = vec.size()-1;
    while(l < r){
        int m = (l+r)/2;
        for(int i = m+1; i <= r; ++i)
            col[vec[i]] = 1;
        for(int i = 0; i < u.size(); ++i)
            if(col[u[i]] != col[v[i]])
                w[i] = 1;
        if(ask(w) == begval)
            r = m;
        else
            l = m+1;
        for(int i = 0; i < u.size(); ++i)
            w[i] = 0;
        for(int i = m+1; i <= r; ++i)
            col[vec[i]] = 0;
    }
    return vec[l];
}
void find_pair(int N, std::vector<int> U, std::vector<int> V, int A, int B) {
    u = U;
    v = V;
    w.resize(U.size());
    for(int i = 0; i < U.size(); ++i){
        g[U[i]].pb({V[i], i});
        g[V[i]].pb({U[i], i});
    }
    begval = ask(w);
    int l = 0, r = U.size()-1;
    while(l < r){
        int m = (l+r)/2;
        for(int i = l; i <= m; ++i)
            w[i] = 1;
        if(ask(w) != begval)
            r = m;
        else
            l = m+1;
        for(int i = l; i <= m; ++i)
            w[i] = 0;
    }
    int e = l;
    queue<pii> q;
    q.push({0, U[e]});
    q.push({1, V[e]});
    vis[U[e]] = vis[V[e]] = 1;
    while(q.size()){
        int type = q.front().ff;
        int v = q.front().ss;
        q.pop();
        vec[type].pb(v);
        for(auto u : g[v])
            if(vis[u.ff] == 0){
                vis[u.ff] = 1;
                q.push({type, u.ff});
            }
    }
    answer(get(vec[0]), get(vec[1]));
}   

Compilation message (stderr)

highway.cpp: In function 'int get(std::vector<int>&)':
highway.cpp:29:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   29 |         for(int i = 0; i < u.size(); ++i)
      |                        ~~^~~~~~~~~~
highway.cpp:36:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   36 |         for(int i = 0; i < u.size(); ++i)
      |                        ~~^~~~~~~~~~
highway.cpp: In function 'void find_pair(int, std::vector<int>, std::vector<int>, int, int)':
highway.cpp:47:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   47 |     for(int i = 0; i < U.size(); ++i){
      |                    ~~^~~~~~~~~~

• Subtask 1: 5 / 5
• Subtask 2: 7 / 7
• Subtask 3: 6 / 6
• Subtask 4: 33 / 33
• Subtask 5: 18 / 18
• Subtask 6: 31 / 31