Submission #935261

#	Time	Username	Problem	Language	Result	Execution time	Memory
935261		VinhLuu	Factories (JOI14_factories)	C++17	0 / 100	15 ms	39512 KiB

factories

// REPUTATION RATING = -100
 
#include "factories.h"
 
#include <bits/stdc++.h>
//#define int long long
#define ll long long
#define fi first
#define se second
#define pb push_back
#define all(lmao) lmao.begin(), lmao.end()
 
using namespace std;
 
typedef pair<int,int> pii;
typedef tuple<int,int,int> tp;
const int N = 5e5 + 5;
const int oo = 1e9;
const int mod = 1e9 + 7;
 
int n, q, st[N << 1], f[N][22], in[N], en[N], demin, a[N];
 
ll d[N];
 
vector<pii> p[N];
 
void dfs(int u,int v){
    in[u] = ++demin;
    a[in[u]] = u;
    if(u == 1) for(int i = 0; i <= 20; i ++) f[u][i] = u;
    else{
        f[u][0] = v;
        for(int i = 1; i <= 20; i ++) f[u][i] = f[f[u][i - 1]][i - 1];
    }
    for(auto jj : p[u]){
        int j = jj.fi;
        int w = jj.se;
        if(j == v) continue;
        d[j] = d[u] + w;
        dfs(j, u);
    }
    en[u] = demin;
}
 
bool kt(int u,int v){
    return in[u] <= in[v] && in[v] <= en[u];
}
 
int lca(int u,int v){
    if(kt(u, v)) return u;
    else{
        int kq = u;
        for(int i = 20; i >= 0; i --){
            if(kt(f[u][i], v)) kq = f[u][i];
            else u = f[u][i];
        }
        return kq;
    }
}
 
void update(int i,int x){
    i += n - 1;
    st[i] = x;
    while(i > 1){
        i /= 2;
        st[i] = min(st[i << 1], st[i << 1|1]);
    }
}
 
int get(int l,int r){
    r++;
    int ret = 1e9;
    for(l += n - 1, r += n - 1; l < r; l /= 2, r /= 2){
        if(l & 1) ret = min(ret, st[l ++]);
        if(r & 1) ret = min(ret, st[-- r]);
    }
    return ret;
}
 
void Init(int N, int A[], int B[], int D[]){
    n = N;
    for(int i = 0; i < n - 1; i ++){
        int x = A[i] + 1, y = B[i] + 1, w = D[i];
        p[x].pb({y, w});
        p[y].pb({x, w});
    }
    dfs(1, 0);
    for(int i = 1; i <= 2 * n; i ++) st[i] = oo;
}
 
long long Query(int S, int X[], int T, int Y[]){
    for(int i = 0; i < S; i ++) X[i]++;
    for(int i = 0; i < T; i ++) Y[i]++;
    ll ans = (ll)1e16;
    for(int time = 0; time <= 1; time ++){
        for(int i = 0; i < S; i ++){
            int j = X[i];
            update(in[j], in[j]);
        }
        for(int i = 0; i < T; i ++){
            int j = Y[j];
            int u = get(in[j], en[j]);
            if(u == oo) continue;
            u = a[u];
            ans = min(ans, d[j] + d[u] - 1LL * 2 * d[lca(u, j)]);
        }
        for(int i = 0; i < S; i ++){
            int j = X[i];
            update(in[j], oo);
        }
        if(time == 0){
            swap(S, T);
            swap(X, Y);
        }
    }
    return ans;
}
 
//#define LOCAL
 
#ifdef LOCAL
 
signed main(){
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
 
    #define task "v"
    if(fopen(task ".inp","r")){
        freopen(task ".inp","r",stdin);
        freopen(task ".out","w",stdout);
    }
 
//    cin >> n >> q;
//    for(int i = 1; i <= 2 * n; i ++) st[i] = (int)1e9;
//    for(int i = 1; i <= n - 1; i ++){
//        int x, y; cin >> x >> y;
//        p[x].pb(y);
//        p[y].pb(x);
//    }
//    dfs(1, 0);
}
#endif // LOCAL
 

Compilation message (stderr)

factories.cpp: In function 'long long int Query(int, int*, int, int*)':
factories.cpp:101:23: warning: 'j' may be used uninitialized in this function [-Wmaybe-uninitialized]
  101 |             int j = Y[j];
      |                       ^

• Subtask 1: 0 / 15
• Subtask 2: 0 / 18
• Subtask 3: 0 / 67