Submission #667469

# Submission time Handle Problem Language Result Execution time Memory
667469 2022-12-01T12:58:11 Z Soul234 Mergers (JOI19_mergers) C++14
0 / 100
65 ms 34480 KB
#include<bits/stdc++.h>
using namespace std;

void DBG() { cerr << "]\n"; }
template<class H, class... T> void DBG(H h, T... t) {
    cerr << h; if(sizeof...(t)) cerr << ", ";
    DBG(t...);
}
#ifdef LOCAL
#define dbg(...) cerr << "[" << #__VA_ARGS__ << "]: [", DBG(__VA_ARGS__)
#else
#define dbg(...) 0
#endif // LOCAL

#define FOR(i,a,b) for(int i = (a) ; i<(b) ; i++)
#define F0R(i,a) FOR(i,0,a)
#define ROF(i,a,b) for(int i = (b)-1 ; i>=(a) ; i--)
#define R0F(i,a) ROF(i,0,a)
#define each(e,a) for(auto &e : (a))
#define sz(v) (int)(v).size()
#define all(v) (v).begin(),(v).end()
#define rall(v) (v).rbegin(),(v).rend()
#define pb push_back
#define tcT template<class T
#define nl "\n"
#define fi first
#define se second

using ll = long long;
using vi = vector<int>;
using pi = pair<int,int>;
using str = string;
using db = long double;
tcT> using V = vector<T>;
tcT> using pqg = priority_queue<T,vector<T>,greater<T>>;

void setIO(string NAME = "") {
    cin.tie(0)->sync_with_stdio(0);
    if(sz(NAME)) {
        freopen((NAME + ".inp").c_str(),"r",stdin);
        freopen((NAME + ".out").c_str(),"w",stdout);
    }
}

tcT> bool ckmin(T&a, const T&b) {
    return b < a ? a=b,1 : 0; }
tcT> bool ckmax(T&a, const T&b) {
    return b > a ? a=b,1 : 0; }

const int MOD = 1e9 + 7;
const ll INF = 1e18;

const int MX = 5e5+5;

int N, K;
int col[MX];

bool ok[MX];

vi lst[MX];

int cc = 0;

int ccid[MX];

vi adj[MX];

void dfs(int u, int p, int req) {
    ccid[u] = cc;
    each(v, adj[u]) if(v != p && !ccid[v] && col[v] == req) {
        dfs(v, u, req);
    }
}

int deg[MX];
pi eds[MX];
int cnt[MX];

void solve() {
    cin >> N >> K;
    F0R(i, N-1) {
        int u, v;
        cin >> u >> v;
        eds[i] = {u, v};
        adj[u].pb(v);
        adj[v].pb(u);
    }
    FOR(i,1,N+1) {
        cin >> col[i];
        lst[col[i]].pb(i);
    }
    if(K == 1) {
        cout << "0\n";
        return;
    }
    FOR(i,1,K+1) {
        each(u, lst[i]) if(!ccid[u]) {
            cc++;
            cnt[i]++;
            dfs(u, -1, i);
        }
    }

    F0R(i, N-1) {
        int u = eds[i].fi, v = eds[i].se;
        u = ccid[u], v = ccid[v];
        if(u != v) {
            deg[u]++;
            deg[v]++;
        }
    }

    int ans = 0;

    FOR(i,1,K+1) if(cnt[i] == 1 && deg[ccid[lst[i][0]]] == 1) {
        ans++;
    }

    cout << (ans+1)/2 << nl;
}

int main() {
    setIO();

    int t=1;
    //cin>>t;
    while(t-->0) {
        solve();
    }

    return 0;
}

Compilation message

mergers.cpp: In function 'void setIO(std::string)':
mergers.cpp:40:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   40 |         freopen((NAME + ".inp").c_str(),"r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
mergers.cpp:41:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   41 |         freopen((NAME + ".out").c_str(),"w",stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 13 ms 23836 KB Output is correct
2 Incorrect 14 ms 23836 KB Output isn't correct
3 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 13 ms 23836 KB Output is correct
2 Incorrect 14 ms 23836 KB Output isn't correct
3 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 13 ms 23836 KB Output is correct
2 Incorrect 14 ms 23836 KB Output isn't correct
3 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 54 ms 31220 KB Output is correct
2 Correct 65 ms 34480 KB Output is correct
3 Incorrect 15 ms 24020 KB Output isn't correct
4 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 13 ms 23836 KB Output is correct
2 Incorrect 14 ms 23836 KB Output isn't correct
3 Halted 0 ms 0 KB -