제출 #1293135

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1293135		trandaihao5555	경주 (Race) (IOI11_race)	C++20	0 / 100	177 ms	327680 KiB

race

#include <bits/stdc++.h>
#include "race.h"

//#define int long long

#define debug     cout << "ok\n";
#define SQR(x)    (1LL * ((x) * (x)))
#define MASK(i)   (1LL << (i))
#define BIT(x, i) (((x) >> (i)) & 1)
#define fi        first
#define se        second
#define pb        push_back

#define mp make_pair
#define pii pair<int,int>
#define pli pair<ll,int>
#define vi vector<int>

#define FAST ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);

typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
typedef unsigned int ui;

using namespace std;

const int M = 1e9 + 7;
const int INF = 1e9 + 7;
const ll INFLL = (ll)2e18 + 7LL;
const ld PI = acos(-1);

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

template<class _, class __>
    bool minimize(_ &x, const __ y){
        if(x > y){
            x = y;
            return true;
        } else return false;
    }
template<class _, class __>
    bool maximize(_ &x, const __ y){
        if(x < y){
            x = y;
            return true;
        } else return false;
    }

template<class _,class __>
    void Add(_ &x, const __ y) {
        x += y;
        if (x >= M) {
            x -= M;
        }
        return;
    }

template<class _,class __>
    void Diff(_ &x, const __ y) {
        x -= y;
        if (x < 0) {
            x += M;
        }
        return;
    }

//--------------------------------------------------------------

const int MaxN = 1e6+7;

int n,k,sz[MaxN],h[MaxN],res = INF;
long long len[MaxN];
map<long long,int> f,g;
bool isCT[MaxN];
vector<pii> a[MaxN];

void dfs(int u,int p) {
    sz[u] = 0;
    for (pii e : a[u]) {
        int v = e.se;
        if (v == p || isCT[v]) continue;
        dfs(v,u);
        sz[u] += sz[v];
    }
}

int GetCen(int u,int p,int r) {
    for (pii e : a[u]) {
        int v = e.fi;
        if (v == p || isCT[v]) continue;
        if (sz[v]*2 >= sz[r]) return GetCen(v,u,r);
    }
    return u;
}

void dfss(int u,int p) {
    if (f.find(k-len[u]) != f.end()) minimize(res,f[k-len[u]] + h[u]);
    if (g.find(len[u]) == g.end()) g[len[u]] = h[u];
    else minimize(g[len[u]],h[u]);
    for (pii e : a[u]) {
        int v = e.fi;
        int w = e.se;
        if (v == p || isCT[v]) continue;
        h[v] = h[u] + 1;
        len[v] = len[u] + w;
        dfss(v,u);
    }
}

void CenTroid(int u) {
    dfs(u,-1);
    u = GetCen(u,-1,u);
    isCT[u] = true;

    f.clear();
    f[0] = 0;
    for (pii e : a[u]) {
        int v = e.fi;
        if (isCT[v]) continue;
        g.clear();
        len[v] = e.se;
        h[v] = 1;
        dfss(v,-1);
        for (pii tmp : g) {
            if (f.find(tmp.fi) == f.end()) f[tmp.fi] = tmp.se;
            else minimize(f[tmp.fi],tmp.se);
        }
    }

    for (pii e : a[u]) {
        int v = e.fi;
        if (isCT[v]) continue;
        CenTroid(v);
    }
}

int best_path(int N,int K,int h[][2],int l[]) {
    k = K;
    n = n;
    for (int i=0;i<N-1;i++) {
        int u = h[i][0];
        int v = h[i][1];
        int w = l[i];
        a[u].pb(mp(v,w));
        a[v].pb(mp(u,w));
    }
    CenTroid(1);
    if (res >= INF) return -1;
    else return res;
}

//void sol() {
//
//}
//
//signed main() {
////    freopen("test.inp","r",stdin);
////    freopen("test.out","w",stdout);
//    FAST
//    int t=1;
////    cin >> t;
//    while (t--) sol();
//}

• Subtask 1: 0 / 9
• Subtask 2: 0 / 12
• Subtask 3: 0 / 22
• Subtask 4: 0 / 57