Submission #417910

# Submission time Handle Problem Language Result Execution time Memory
417910 2021-06-04T13:42:30 Z nicolaalexandra Joker (BOI20_joker) C++14
25 / 100
1056 ms 9588 KB
#include <bits/stdc++.h>
#define DIM 400010
using namespace std;

int fth[DIM],Size[DIM],dp[DIM];
pair <int,int> mch[DIM];
deque <pair<int,int> > s;
int n,m,q,x,y,i,first;

int get_rad (int x){
    while (fth[x] != x)
        x = fth[x];
    return x;
}

int uneste (int x, int y, int &cnt){
    int radx = get_rad (x), rady = get_rad (y);
    if (radx == rady)
        return 0;

    cnt++;

    if (Size[radx] < Size[rady])
        swap (radx,rady);

    s.push_back(make_pair(radx,rady));
    Size[radx] += Size[rady];
    fth[rady] = radx;

    return 1;
}

void undo(){
    int x = s.back().first, y = s.back().second;
    s.pop_back();
    Size[x] -= Size[y];
    fth[y] = y;
}

void solve (int st, int dr, int opt_st, int opt_dr){
    if (st > dr)
        return;
    int mid = (st+dr)>>1, opt_mid;

    /// adaug tot pana la mid
    int ok = 0;
    int cnt = 0; /// de cate ori fac unirile efective
    for (int i=max(1,st-1);i<mid;i++){
        int x = mch[i].first, y = mch[i].second;

        if (!uneste(x,y,cnt)){
            ok = 1;
            break;
        } else undo(), cnt--;

        uneste (x,y+n,cnt);
        uneste (x+n,y,cnt);
    }

    if (ok || first){ /// se strica proprietatea de bipartit pana sa ajung la mid
        dp[mid] = m+1;
        opt_mid = m+1;
        if (!first)
            first = mid;

    } else {
        for (opt_mid = min(m,opt_dr); opt_mid >= mid ; opt_mid--){

            /// adaug muchia asta si vad daca se pastreaza propr de bipartit
            int x = mch[opt_mid].first, y = mch[opt_mid].second;

            if (!uneste(x,y,cnt)){
                break;
            } else undo(),cnt--;

            uneste (x,y+n,cnt); /// muchiile astea vin ca la 2sat
            uneste (x+n,y,cnt);
        }

        dp[mid] = opt_mid;
    }

    /// trb sa construiesc padurile special pt urmatorul apel

    /// dau undo la toate si mai adaug dupa de la opt_mid la opt_dr
    for (int i=1;i<=cnt;i++)
        undo();

    int val = 0;
    for (int i=opt_dr;i>opt_mid;i--){
        int x = mch[i].first, y = mch[i].second;
        uneste (x,y+n,val);
        uneste (x+n,y,val);
    }

    solve (st,mid-1,opt_st,opt_mid);

    for (int i=1;i<=val;i++)
        undo();

    int val2 = 0;
    for (int i=st;i<mid;i++){
        int x = mch[i].first, y = mch[i].second;
        uneste (x,y+n,val2);
        uneste (x+n,y,val2);
    }

    solve (mid+1,dr,opt_mid,opt_dr);

    for (int i=1;i<=val2;i++)
        undo();
}



int main (){

    //ifstream cin ("date.in");
    //ofstream cout ("date.out");

    cin>>n>>m>>q;
    for (i=1;i<=m;i++)
        cin>>mch[i].first>>mch[i].second;

    for (i=1;i<=2*n;i++)
        fth[i] = i, Size[i] = 1;

    solve (1,m,1,m+1);

    for (;q--;){
        cin>>x>>y;

        if (y >= dp[x])
            cout<<"NO\n";
        else cout<<"YES\n";

        /*if (dp[x] == m+1 || dp[x] > y)
            cout<<"YES\n";
        else cout<<"NO\n";*/
    }


    return 0;
}
# Verdict Execution time Memory Grader output
1 Correct 1 ms 204 KB Output is correct
2 Correct 1 ms 204 KB Output is correct
3 Correct 0 ms 204 KB Output is correct
4 Correct 0 ms 204 KB Output is correct
5 Correct 1 ms 204 KB Output is correct
6 Incorrect 1 ms 204 KB Output isn't correct
7 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 1 ms 204 KB Output is correct
2 Correct 1 ms 204 KB Output is correct
3 Correct 0 ms 204 KB Output is correct
4 Correct 0 ms 204 KB Output is correct
5 Correct 1 ms 204 KB Output is correct
6 Incorrect 1 ms 204 KB Output isn't correct
7 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 1 ms 204 KB Output is correct
2 Correct 1 ms 204 KB Output is correct
3 Correct 795 ms 6400 KB Output is correct
4 Correct 1032 ms 9588 KB Output is correct
5 Correct 853 ms 9040 KB Output is correct
6 Correct 781 ms 5872 KB Output is correct
7 Correct 809 ms 5904 KB Output is correct
8 Correct 974 ms 5328 KB Output is correct
9 Correct 934 ms 6704 KB Output is correct
10 Correct 1056 ms 9284 KB Output is correct
11 Correct 866 ms 6556 KB Output is correct
12 Correct 929 ms 8736 KB Output is correct
13 Correct 879 ms 3812 KB Output is correct
14 Correct 954 ms 5084 KB Output is correct
15 Correct 988 ms 7696 KB Output is correct
16 Correct 1037 ms 9072 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 204 KB Output is correct
2 Correct 1 ms 204 KB Output is correct
3 Correct 0 ms 204 KB Output is correct
4 Correct 0 ms 204 KB Output is correct
5 Correct 1 ms 204 KB Output is correct
6 Incorrect 1 ms 204 KB Output isn't correct
7 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 1 ms 204 KB Output is correct
2 Correct 1 ms 204 KB Output is correct
3 Correct 0 ms 204 KB Output is correct
4 Correct 0 ms 204 KB Output is correct
5 Correct 1 ms 204 KB Output is correct
6 Incorrect 1 ms 204 KB Output isn't correct
7 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 1 ms 204 KB Output is correct
2 Correct 1 ms 204 KB Output is correct
3 Correct 0 ms 204 KB Output is correct
4 Correct 0 ms 204 KB Output is correct
5 Correct 1 ms 204 KB Output is correct
6 Incorrect 1 ms 204 KB Output isn't correct
7 Halted 0 ms 0 KB -