Submission #1100336

#	Time	Username	Problem	Language	Result	Execution time	Memory
1100336		khoile08	Race (IOI11_race)	C++14	Compilation error	0 ms	0 KiB

race

#include <bits/stdc++.h>
using namespace std;
#define faster ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
#define int long long
#define FOR(i,a,b) for(int i = a; i <= b; i++)
#define FOD(i,a,b) for(int i = a; i >= b; i--)
#define fi first
#define se second
#define pb push_back
#define ll long long
#define ull unsigned long long
#define lcm(a,b) (a*b)/__gcd(a,b)
#define ii pair<int,int>
#define iii pair<int,pair<int,int>>
#define iv pair<pair<int,int>,pair<int,int>>

const int inf = 1e9;
const ll INF = 1e18;
const int mod = 1e9 + 7;
const int N = 2e5 + 105;

const int dx[] = {-1,0,1,0};
const int dy[] = {0,1,0,-1};
const int dxx[] = {-1,-1,0,1,1,1,0,-1};
const int dyy[] = {0,1,1,1,0,-1,-1,-1};

int n, k, ans;
vector<ii> g[N];
int sze[N];
map<int,int> best;
bool is_centroid[N];

void dfs(int u, int p)
{
    sze[u] = 1;
    for(ii H : g[u])
    {
        if(H.fi != p && !is_centroid[H.fi])
        {
            dfs(H.fi,u);
            sze[u] += sze[H.fi];
        }
    }
}

int find_centroid(int u, int p, int s)
{
    for(ii H : g[u])
        if(H.fi != p && !is_centroid[H.fi] && sze[H.fi] > s / 2)
            return find_centroid(H.fi,u,s);
    return u;
}

void cal_dis(int u, int p, int w, int h, int type)
{
    if(w > k)
        return;
    if(type == 2)
    {
        if(best.count(k-w))
        {
           ans = min(ans, best[k-w]+h);
        }
    }
    else
    {
        if(!best.count(w))
            best[w] = h;
        else
            best[w] = min(best[w], h);
    }
    for(ii H : g[u])
        if(H.fi != p && !is_centroid[H.fi])
            cal_dis(H.fi,u,w+H.se,h+1,type);
}

void build_centroid(int u)
{
    dfs(u,-1);
    int centroid = find_centroid(u,-1,sze[u]);
    best[0] = 0;
    is_centroid[centroid] = 1;
    for(ii H : g[centroid])
    {
        if(is_centroid[H.fi])
            continue;
        cal_dis(H.fi,centroid,H.se,1,2);
        cal_dis(H.fi,centroid,H.se,1,1);
    }
    best.clear();
    for(ii H : g[centroid])
        if(!is_centroid[H.fi])
            build_centroid(H.fi);
}

void solve()
{
    ans = INF;
    build_centroid(1);
}

//void input()
//{
//    //freopen("TEST.INP", "r", stdin);
//    //freopen("TEST.OUT", "w", stdout);
//    cin >> n >> k;
//    FOR(i,1,n-1)
//    {
//        int u, v, w;
//        cin >> u >> v >> w;
////        u++;
////        v++;
//        g[u].pb({v,w});
//        g[v].pb({u,w});
//    }
//}

//signed main()
//{
//    faster
//    input();
//    solve();
//}

int best_path(int N, int K, int H[][2], int L[])
{
    n = N;
    k = K;
    FOR(i,1,n-1)
    {
        int u = H[i][0];
        int v = H[i][1];
        int w = L[i];
        g[u].pb({v,w});
        g[v].pb({u,w});
    }
    solve();
    return (ans == INF ? -1 : ans);
}

Compilation message (stderr)

/usr/bin/ld: /tmp/ccUC7N7R.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