oj.uz

Submission #799778

# Submission time Handle Problem Language Result Execution time Memory
799778 2023-08-01T02:05:57 Z Alish Mergers (JOI19_mergers) C++14
0 / 100
 121 ms 43500 KB 
#include <bits/stdc++.h>

using namespace std;

typedef long long int	ll;
typedef long double	ld;
typedef pair<int, int>	pii;
typedef pair<ll, ll>	pll;


#define F		        first
#define S		        second
#define pb		        push_back
#define endl            '\n'
#define Mp		        make_pair
#define all(x)          x.begin(), x.end()
#define debug(x)        cerr << #x << " = " << x << endl
#define set_dec(x)	    cout << fixed << setprecision(x);
#define fast_io         ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
#define file_io         freopen("in.txt" , "r+" , stdin) ; freopen("out.txt" , "w+" , stdout);


ll mod = 998244353;

ll power(ll a, ll b)
{
    return (!b ? 1 : (b & 1 ? a * power(a * a % mod, b / 2) % mod : power(a * a % mod, b / 2) % mod));
}

const int N = 5e5+23, L =23 ;

vector<int>g[N], buc[N];
int st[N], h[N], par[N][L], sz[N], sum[N], is[N];
int ans;
int n , k ;
int a[N];

int tim;
void dfs(int v, int p=0){
    sz[v]=1;
    st[v]=++tim;
    for (int u: g[v]) {
        if(u==p)continue;
        h[u]=h[v]+1;
        par[u][0]=v;
        dfs(u,v);
        sz[v]+=sz[u];
    }
}

void DFS(int v, int p=0){

    int temp=0;
    for (int u: g[v]){
        if(u==p) continue;
        DFS(u,v);
        temp+=is[u];
        sum[v]+=sum[u];
    }

    if(sum[v]==sz[v]){
        if(temp==0)ans++;
        if(temp==1 && v==1) ans++;
        is[v]=1;
    }
}

int LCA(int v, int u){

    if(h[v]>h[u])swap(u,v);

    int d =h[u]-h[v];
    for (int i=L-1; i>=0; i--) {
        if(d>>i&1) u=par[u][i];
    }

    if(u==v) return v;

    for (int i=L-1; i>=0; i--){
        if(par[u][i]!=par[v][i]){
            v=par[v][i];
            u=par[u][i];
        }
    }

    return par[v][0];

}

int main()
{

    cin>>n>>k;
    for (int i=0; i<n-1; i++){
        int u , v; cin>>v>>u;
        g[v].pb(u);
        g[u].pb(v);
    }
    for (int i=1; i<=n; i++){
        cin>>a[i];
        buc[a[i]].pb(i);
    }

    dfs(1);

    for (int w=1; w<=k; w++){
        vector<pii> vec;
        for (int i: buc[w]) vec.pb({st[i], i});
        sort(all(vec));
        int lca=LCA(vec[0].S, vec.back().S);
        sum[lca]+=buc[w].size();
    }

    DFS(1);
    cout<<(ans+1)/2<<endl;

}

Subtask #1
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 12 ms 23764 KB Output is correct
2 Incorrect 12 ms 23800 KB Output isn't correct
3 Halted 0 ms 0 KB -

Subtask #2
0 / 24.0

# Verdict Execution time Memory Grader output
1 Correct 12 ms 23764 KB Output is correct
2 Incorrect 12 ms 23800 KB Output isn't correct
3 Halted 0 ms 0 KB -

Subtask #3
0 / 14.0

# Verdict Execution time Memory Grader output
1 Correct 12 ms 23764 KB Output is correct
2 Incorrect 12 ms 23800 KB Output isn't correct
3 Halted 0 ms 0 KB -

Subtask #4
0 / 22.0

# Verdict Execution time Memory Grader output
1 Correct 86 ms 39864 KB Output is correct
2 Correct 121 ms 43500 KB Output is correct
3 Incorrect 14 ms 24276 KB Output isn't correct
4 Halted 0 ms 0 KB -

Subtask #5
0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 12 ms 23764 KB Output is correct
2 Incorrect 12 ms 23800 KB Output isn't correct
3 Halted 0 ms 0 KB -