Submission #525396

#	Time	Username	Problem	Language	Result	Execution time	Memory
525396		idas	Stations (IOI20_stations)	C++17	100 / 100	994 ms	772 KiB

stations

#include <bits/stdc++.h>
#define FAST_IO ios_base::sync_with_stdio(0); cin.tie(nullptr); cout.tie(nullptr)
#define FOR(i, begin, end) for(int i = (begin); i < (end); i++)
#define TSTS int ttt; cin >> ttt; while(ttt--) solve()
#define all(x) (x).begin(), (x).end()
#define le(vec) vec[vec.size()-1]
#define sz(x) ((int)((x).size()))
#define pb push_back
#define s second
#define f first

using namespace std;
typedef long long ll;
typedef long double ld;
typedef vector<int> vi;
typedef map<int, int> mii;
typedef pair<int, int> pii;
typedef pair<long long, long long> pll;
typedef pair<long double, long double> pdd;

const int INF=1e9, MOD=1e9+7, mod=998244353;
const ll LINF=1e18;

void setIO()
{
    FAST_IO;
}

void setIO(string s)
{
    FAST_IO;
    freopen((s+".in").c_str(), "r", stdin);
    freopen((s+".out").c_str(), "w", stdout);
}

const int N=1e3+10;
int dp[N], lb[N], lst;
bool v[N];
vi ad[N];

void build(int u, int pst)
{
    for(auto x : ad[u]){
        if(x==pst) continue;
        build(x, u);
        dp[u]+=dp[x];
    }
    dp[u]++;
}

void dfs(int u, int pst, bool mx)
{
    if(mx){
        while(v[lst]) lst--;
        lb[u]=lst;
        v[lst]=true;
    }
    for(auto x : ad[u]){
        if(x==pst) continue;
        if(mx){
            int now=lb[u];
            while(v[now]) now--;
            lb[x]=now-dp[x]+1;
            assert(!v[lb[x]]);
            v[lb[x]]=true;
        }
        dfs(x, u, !mx);
    }
}

vi label(int n, int k, vi uu, vi vv)
{
    FOR(i, 0, n+1) ad[i].clear(), v[i]=false, dp[i]=0, lb[i]=0;
    FOR(i, 0, n-1)
    {
        ad[uu[i]].pb(vv[i]);
        ad[vv[i]].pb(uu[i]);
    }
    lst=n;
    build(0, -1);
    dfs(0, -1, true);
    vi ans;
    FOR(i, 0, n) ans.pb(lb[i]);
    return ans;
}

int find_next_station(int s, int t, vi c)
{
    for(auto x : c){
        if(x==t){
            return t;
        }
    }

    if(s<c[0]){
        if(t<s){
            return le(c);
        }
        FOR(i, 0, sz(c)-1)
        {
            if(c[i]>t){
                return c[i];
            }
        }
        return le(c);
    }
    else{
        if(t>s){
            return c[0];
        }
        for(int i=sz(c)-1; i>0; i--){
            if(c[i]<t){
                return c[i];
            }
        }
        return c[0];
    }
}

/*int main()
{
    setIO();
    /*int nn, kk; cin >> nn >> kk;
    vi ar(nn-1), br(nn-1);
    FOR(i, 0, nn-1)
    {
        cin >> ar[i] >> br[i];
    }

    for(auto x : label(nn, kk, ar, br)){
        cout << x << '\n';
    }*/

    //cout << find_next_station(3, 4, {1,2});
//}

Compilation message (stderr)

stations.cpp:123:5: warning: "/*" within comment [-Wcomment]
  123 |     /*int nn, kk; cin >> nn >> kk;
      |      
stations.cpp: In function 'void setIO(std::string)':
stations.cpp:32:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   32 |     freopen((s+".in").c_str(), "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
stations.cpp:33:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   33 |     freopen((s+".out").c_str(), "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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