Submission #479374

#	Time	Username	Problem	Language	Result	Execution time	Memory
479374		Protostar	Race (IOI11_race)	C++14	Compilation error	0 ms	0 KiB

race

#include <bits/stdc++.h>
//#include <ext/pb_ds/assoc_container.hpp>
//#include <ext/pb_ds/tree_policy.hpp>

//using namespace __gnu_pbds;
using namespace std;

#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
#pragma GCC optimize ("unroll-loops")
#pragma GCC optimize("Ofast")
#pragma GCC optimize ("O3")
#pragma GCC target ("avx")

typedef long long ll;
typedef long double ld;
//typedef tree<int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update> ordered_set;

#define Confundo ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0)
#define minheap priority_queue<int,vector<int>,greater<int>>
#define print2d(dp,n,m) for(int i=0;i<n;i++){for(int j=0;j<m;j++)cout<<dp[i][j]<<" ";cout<<"\n";}
#define ftt int t;cin>>t;for(int tt=1;tt<=t;++tt)
#define Sum(v) accumulate(v.begin(),v.end(),(ll)0)
#define Rev(v) reverse(v.begin(),v.end());
#define Sort(v) sort(v.begin(),v.end());
#define Input(v) for(auto &x:v) cin>>x;
#define Output(v) for(auto x:v) cout<<x<<" ";
#define mem(a, b) memset(a, b, sizeof(a))
#define dbgx(x) cout<<"\nhi "<<x<<"\n"
#define double long double
#define int long long
#define maxheap priority_queue<int>
#define dbg cout<<"\nhi\n"
#define sayy cout<<"YES\n"
#define sayn cout<<"NO\n"
#define pii pair<int,int>
#define mii map<int,int>
#define umii unordered_map<int,int>
#define vii vector<pair<int,int>>
#define vvi vector<vector<int>>
#define vb vector<bool>
#define vi vector<int>
#define pb push_back
#define pf push_front
#define popb pop_back
#define popf pop_front
#define snd second
#define fst first
#define endl "\n"

const int INF    = numeric_limits<int>::max() / 2;
const double PI  = 3.1415926535898;
const int MOD    = 1e9 + 7;
const int LIM    = 2e5 + 5;

// O(log y)
int fpow(int x, int y) {
    int temp;
    if (y == 0)
        return 1;
    temp = fpow(x, y / 2);
    if (y % 2 == 0)
        return (temp * temp) % MOD;
    else
        return (x * ((temp * temp) % MOD)) % MOD;
}

// O(log max(a, b))
int gcd(int a, int b) {
    if (b == 0)
        return a;
    return gcd(b, a % b);
}

set<int> adj[LIM];
int sz[LIM];

int dfsForSize(int u, int p)
{
    sz[u] = 1;

    for (int x : adj[u])
    {
        if (x != p)
            sz[u] += dfsForSize(x, u);
    }

    return sz[u];
}

int findCentroid(int u, int p, int n)
{
    for (int x : adj[u])
    {
        if (x != p)
        {
            if (sz[x] > n / 2)
                return findCentroid(x, u, n);
        }
    }

    return u;
}

void centroidDecomposition(int u, int p)
{
    int n = dfsForSize(u, p);
    int centroid = findCentroid(u, p, n);

    vector<int> v;

    for (int x : adj[centroid])
        v.pb(x);

    for (int x : v)
    {
        adj[x].erase(centroid);
        adj[centroid].erase(x);

        centroidDecomposition(x, centroid);
    }
}

void solve()
{
    for (int i = 0; i < LIM; ++i)
    {
        adj[i].clear();
        sz[i] = 0;
    }

    int n;
    cin >> n;

    for (int i = 0; i < n - 1; ++i)
    {
        int a, b;
        cin >> a >> b;

        adj[a].insert(b);
        adj[b].insert(a);
    }

    n = dfsForSize(1, 0);
    int centroid = findCentroid(1, 0, n);

    cout << centroid << endl;

    return;
}


//*************************************************************************************************************************


int32_t main()
{
    Confundo;

    // ftt
    {
        solve();
    }

    return 0;
}

Compilation message (stderr)

/usr/bin/ld: /tmp/ccnylQZD.o: in function `main':
race.cpp:(.text.startup+0x0): multiple definition of `main'; /tmp/cc0nd4CD.o:grader.cpp:(.text.startup+0x0): first defined here
/usr/bin/ld: /tmp/cc0nd4CD.o: in function `main':
grader.cpp:(.text.startup+0x28): undefined reference to `best_path(int, int, int (*) [2], int*)'
collect2: error: ld returned 1 exit status