Submission #240941

#	Time	Username	Problem	Language	Result	Execution time	Memory
240941		rajarshi_basu	Synchronization (JOI13_synchronization)	C++14	0 / 100	8061 ms	21240 KiB

synchronization

#include <iostream>
#include <vector>
#include <algorithm>
#include <fstream>
#include <queue>
#include <deque>
#include <iomanip>
#include <cmath>
#include <set>
#include <stack>
#include <map>
#include <unordered_map>

#define FOR(i,n) for(int i=0;i<n;i++)
#define FORE(i,a,b) for(int i=a;i<=b;i++)
#define ll long long 
//#define int long long
#define ld long double
#define vi vector<ll>
#define pb push_back
#define ff first
#define ss second
#define ii pair<int,int>
#define iii pair<int,ii>
#define pll pair<ll,ll>
#define il pair<ll,ll>
#define vv vector
#define endl '\n'

using namespace std;

const ll INF=0x3f3f3f3f3f3f3f3f;
const ll llinf=(1LL<<60);
const int inf=(1<<30);
const int MAXN=1e5+50;
const ll mod=1e9+7;

int n,m,q,t;
int tin[MAXN];
int tout[MAXN];
int sparseTable[MAXN][20];

int side1[MAXN];
int side2[MAXN];

vi g[MAXN];


void dfs(int x,int p = -1){
    tin[x] = t++;
    sparseTable[x][0]=p;
    // sparseTable
    for(int i=1;i<17;i++)
        sparseTable[x][i] = sparseTable[sparseTable[x][i-1]][i-1];
    //
    for(auto e: g[x])
        if(e != p)
            dfs(e,x);

    tout[x] = t-1;
}

int BIT[MAXN];
void update(int i,int v){
    for(;i<=n;i+=i&(-i))BIT[i]+=v;
}
int query(int i){
    int ans=0;
    for(;i>=1;i-=i&(-i))ans+=BIT[i];
    return ans;
}
int findRoot(int x){
    int cur=query(tin[x]);
    for(int i=16;i>=0;i--)if(query(tin[sparseTable[x][i]])==cur)x=sparseTable[x][i];
    return x;
}


int main(){
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);

    cin >> n >> m >> q;
    ii all[n-1];
    FORE(i,1,n-1){
        int x,y;
        cin >> x >> y;
        all[i] = {x,y};
        g[x].pb(y);
        g[y].pb(x);
    }
    dfs(1);

    FORE(i,1,n){
        update(tin[i],1);
        update(tout[i]+1,-1);
        side1[i]=1;
    }
    FORE(i,1,n-1)
        if(tin[all[i].ff]>tin[all[i].ss])
            swap(all[i].ff,all[i].ss);

    while(m--){
        int edge;
        cin >> edge;
        int x=all[edge].ff;
        int y=all[edge].ss;
        int z=findRoot(x);
        if(side2[edge]==-1){
            update(tin[y],1);
            update(tout[y]+1,-1);
            side2[edge]=side1[y]=side1[z];
        }
        else{
            update(tin[y],-1);
            update(tout[y]+1,1);
            side1[z]+=side1[y]-side2[edge];
            side2[edge]=-1;
        }
    }
    while(q--){
        int x;
        cin >> x;
        cout << side1[findRoot(x)] << endl;
    }
    return 0;
}

• Subtask 1: 0 / 10
• Subtask 2: 0 / 20
• Subtask 3: 0 / 10
• Subtask 4: 0 / 20
• Subtask 5: 0 / 40