#876934 (C++17) No.2337 Equidistant

提出ソース

結果

問題	No.2337 Equidistant
ユーザー	heno239
提出日時	2023-06-02 21:42:54
言語	C++17 (gcc 12.3.0 + boost 1.83.0)
結果	AC
実行時間	1,682 ms / 4,000 ms
コード長	9,582 bytes
コンパイル時間	2,740 ms
コンパイル使用メモリ	166,580 KB
実行使用メモリ	74,816 KB
最終ジャッジ日時	2024-06-08 22:36:59
合計ジャッジ時間	17,361 ms
ジャッジサーバーID （参考情報）	judge1 / judge3

このコードへのチャレンジ
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テストケース

テストケース表示

入力	結果	実行時間実行使用メモリ
testcase_00	AC	19 ms 11,716 KB
testcase_01	AC	19 ms 11,776 KB
testcase_02	AC	19 ms 11,776 KB
testcase_03	AC	19 ms 11,904 KB
testcase_04	AC	20 ms 11,648 KB
testcase_05	AC	19 ms 11,776 KB
testcase_06	AC	21 ms 12,236 KB
testcase_07	AC	21 ms 12,236 KB
testcase_08	AC	22 ms 12,104 KB
testcase_09	AC	21 ms 12,236 KB
testcase_10	AC	21 ms 12,160 KB
testcase_11	AC	580 ms 56,552 KB
testcase_12	AC	584 ms 56,528 KB
testcase_13	AC	563 ms 56,536 KB
testcase_14	AC	569 ms 56,488 KB
testcase_15	AC	569 ms 56,500 KB
testcase_16	AC	605 ms 56,592 KB
testcase_17	AC	586 ms 56,504 KB
testcase_18	AC	604 ms 56,480 KB
testcase_19	AC	583 ms 56,576 KB
testcase_20	AC	565 ms 56,380 KB
testcase_21	AC	997 ms 74,816 KB
testcase_22	AC	417 ms 57,720 KB
testcase_23	AC	454 ms 57,960 KB
testcase_24	AC	1,357 ms 68,736 KB
testcase_25	AC	495 ms 57,856 KB
testcase_26	AC	1,682 ms 68,528 KB
testcase_27	AC	523 ms 57,984 KB
testcase_28	AC	529 ms 57,984 KB

権限があれば一括ダウンロードができます

ソースコード

raw source code

#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
#include<iostream>
#include<string>
#include<cstdio>
#include<vector>
#include<cmath>
#include<algorithm>
#include<functional>
#include<iomanip>
#include<queue>
#include<ciso646>
#include<random>
#include<map>
#include<set>
#include<bitset>
#include<stack>
#include<unordered_map>
#include<unordered_set>
#include<utility>
#include<cassert>
#include<complex>
#include<numeric>
#include<array>
#include<chrono>
using namespace std;

//#define int long long
typedef long long ll;

typedef unsigned long long ul;
typedef unsigned int ui;
//ll mod = 1;
constexpr ll mod = 998244353;
//constexpr ll mod = 1000000007;
const int mod17 = 1000000007;
const ll INF = mod * mod;
typedef pair<int, int>P;

#define rep(i,n) for(int i=0;i<n;i++)
#define per(i,n) for(int i=n-1;i>=0;i--)
#define Rep(i,sta,n) for(int i=sta;i<n;i++)
#define rep1(i,n) for(int i=1;i<=n;i++)
#define per1(i,n) for(int i=n;i>=1;i--)
#define Rep1(i,sta,n) for(int i=sta;i<=n;i++)
#define all(v) (v).begin(),(v).end()
typedef pair<ll, ll> LP;

using ld = long double;
typedef pair<ld, ld> LDP;
const ld eps = 1e-10;
const ld pi = acosl(-1.0);

template<typename T>
void chmin(T& a, T b) {
    a = min(a, b);
}
template<typename T>
void chmax(T& a, T b) {
    a = max(a, b);
}
template<typename T>
vector<T> vmerge(vector<T>& a, vector<T>& b) {
    vector<T> res;
    int ida = 0, idb = 0;
    while (ida < a.size() || idb < b.size()) {
        if (idb == b.size()) {
            res.push_back(a[ida]); ida++;
        }
        else if (ida == a.size()) {
            res.push_back(b[idb]); idb++;
        }
        else {
            if (a[ida] < b[idb]) {
                res.push_back(a[ida]); ida++;
            }
            else {
                res.push_back(b[idb]); idb++;
            }
        }
    }
    return res;
}
template<typename T>
void cinarray(vector<T>& v) {
    rep(i, v.size())cin >> v[i];
}
template<typename T>
void coutarray(vector<T>& v) {
    rep(i, v.size()) {
        if (i > 0)cout << " "; cout << v[i];
    }
    cout << "\n";
}
ll mod_pow(ll x, ll n, ll m = mod) {
    if (n < 0) {
        ll res = mod_pow(x, -n, m);
        return mod_pow(res, m - 2, m);
    }
    if (abs(x) >= m)x %= m;
    if (x < 0)x += m;
    //if (x == 0)return 0;
    ll res = 1;
    while (n) {
        if (n & 1)res = res * x % m;
        x = x * x % m; n >>= 1;
    }
    return res;
}
//mod should be <2^31
struct modint {
    int n;
    modint() :n(0) { ; }
    modint(ll m) {
        if (m < 0 || mod <= m) {
            m %= mod; if (m < 0)m += mod;
        }
        n = m;
    }
    operator int() { return n; }
};
bool operator==(modint a, modint b) { return a.n == b.n; }
bool operator<(modint a, modint b) { return a.n < b.n; }
modint operator+=(modint& a, modint b) { a.n += b.n; if (a.n >= mod)a.n -= (int)mod; return a; }
modint operator-=(modint& a, modint b) { a.n -= b.n; if (a.n < 0)a.n += (int)mod; return a; }
modint operator*=(modint& a, modint b) { a.n = ((ll)a.n * b.n) % mod; return a; }
modint operator+(modint a, modint b) { return a += b; }
modint operator-(modint a, modint b) { return a -= b; }
modint operator*(modint a, modint b) { return a *= b; }
modint operator^(modint a, ll n) {
    if (n == 0)return modint(1);
    modint res = (a * a) ^ (n / 2);
    if (n % 2)res = res * a;
    return res;
}

ll inv(ll a, ll p) {
    return (a == 1 ? 1 : (1 - p * inv(p % a, a)) / a + p);
}
modint operator/(modint a, modint b) { return a * modint(inv(b, mod)); }
modint operator/=(modint& a, modint b) { a = a / b; return a; }
const int max_n = 1 << 20;
modint fact[max_n], factinv[max_n];
void init_f() {
    fact[0] = modint(1);
    for (int i = 0; i < max_n - 1; i++) {
        fact[i + 1] = fact[i] * modint(i + 1);
    }
    factinv[max_n - 1] = modint(1) / fact[max_n - 1];
    for (int i = max_n - 2; i >= 0; i--) {
        factinv[i] = factinv[i + 1] * modint(i + 1);
    }
}
modint comb(int a, int b) {
    if (a < 0 || b < 0 || a < b)return 0;
    return fact[a] * factinv[b] * factinv[a - b];
}
modint combP(int a, int b) {
    if (a < 0 || b < 0 || a < b)return 0;
    return fact[a] * factinv[a - b];
}

ll gcd(ll a, ll b) {
    a = abs(a); b = abs(b);
    if (a < b)swap(a, b);
    while (b) {
        ll r = a % b; a = b; b = r;
    }
    return a;
}
template<typename T>
void addv(vector<T>& v, int loc, T val) {
    if (loc >= v.size())v.resize(loc + 1, 0);
    v[loc] += val;
}
/*const int mn = 2000005;
bool isp[mn];
vector<int> ps;
void init() {
    fill(isp + 2, isp + mn, true);
    for (int i = 2; i < mn; i++) {
        if (!isp[i])continue;
        ps.push_back(i);
        for (int j = 2 * i; j < mn; j += i) {
            isp[j] = false;
        }
    }
}*/

//[,val)
template<typename T>
auto prev_itr(set<T>& st, T val) {
    auto res = st.lower_bound(val);
    if (res == st.begin())return st.end();
    res--; return res;
}

//[val,)
template<typename T>
auto next_itr(set<T>& st, T val) {
    auto res = st.lower_bound(val);
    return res;
}
using mP = pair<modint, modint>;
mP operator+(mP a, mP b) {
    return { a.first + b.first,a.second + b.second };
}
mP operator+=(mP& a, mP b) {
    a = a + b; return a;
}
mP operator-(mP a, mP b) {
    return { a.first - b.first,a.second - b.second };
}
mP operator-=(mP& a, mP b) {
    a = a - b; return a;
}
LP operator+(LP a, LP b) {
    return { a.first + b.first,a.second + b.second };
}
LP operator+=(LP& a, LP b) {
    a = a + b; return a;
}
LP operator-(LP a, LP b) {
    return { a.first - b.first,a.second - b.second };
}
LP operator-=(LP& a, LP b) {
    a = a - b; return a;
}

mt19937 mt(time(0));

const string drul = "DRUL";
string senw = "SENW";
//DRUL,or SENW
//int dx[4] = { 1,0,-1,0 };
//int dy[4] = { 0,1,0,-1 };

//-----------------------------------------

struct lcagraph {
private:
    int n;
    vector<vector<int>> G;
    vector<vector<int>> parent;
    vector<int> depth;
    int root;
    int tmp;
public:
    lcagraph(int n_) {
        n = n_;
        G.resize(n);
        parent.resize(n);
        depth.resize(n);
        tmp = 0;
        int cop = n;
        while (cop) {
            tmp++; cop /= 2;
        }
        rep(i, n)parent[i].resize(tmp);
        root = 0;
    }
    lcagraph() {}
    void init(int n_) {
        n = n_;
        G.resize(n);
        parent.resize(n);
        depth.resize(n);
        tmp = 0;
        int cop = n;
        while (cop) {
            tmp++; cop /= 2;
        }
        rep(i, n)parent[i].resize(tmp);
        root = 0;
    }
    void add_edge(int a, int b) {
        G[a].push_back(b);
        G[b].push_back(a);
    }
    void dfs(int id, int fr, int d) {
        parent[id][0] = fr;
        depth[id] = d;
        rep(j, G[id].size()) {
            int to = G[id][j];
            if (to == fr)continue;
            dfs(to, id, d + 1);
        }
    }
    void complete(int r = 0) {
        root = r;
        dfs(root, -1, 0);
        rep(j, tmp - 1)rep(i, n) {
            if (parent[i][j] < 0)parent[i][j + 1] = -1;
            else parent[i][j + 1] = parent[parent[i][j]][j];
        }
    }
    int lca(int u, int v) {
        if (depth[u] > depth[v])swap(u, v);
        for (int k = 0; k < tmp; k++) {
            if ((depth[v] - depth[u]) >> k & 1) {
                v = parent[v][k];
            }
        }
        if (u == v)return u;
        for (int k = tmp - 1; k >= 0; k--) {
            if (parent[u][k] != parent[v][k]) {
                u = parent[u][k];
                v = parent[v][k];
            }
        }
        return parent[u][0];
    }
    int dep(int x) {
        return depth[x];
    }
    int dist(int x, int y) {
        int l = lca(x, y);
        return depth[x] + depth[y] - 2 * depth[l];
    }
    //from a to b
    int proc_d(int a, int b, int d) {
        int l = lca(a, b);
        int res;
        if (dep(a) - dep(l) >= d) {
            res = a;
            rep(i, tmp) {
                if (d & (1 << i))res = parent[res][i];
            }
        }
        else {
            d = dep(a) + dep(b) - 2 * dep(l) - d;
            res = b;
            rep(i, tmp) {
                if (d & (1 << i))res = parent[res][i];
            }
        }
        return res;
    }
};

void solve() {
    int n, q; cin >> n >> q;
    vector<vector<int>> G(n);
    lcagraph lc(n);
    rep(i, n - 1) {
        int a, b; cin >> a >> b; a--; b--;
        lc.add_edge(a, b);
        G[a].push_back(b);
        G[b].push_back(a);
    }
    lc.complete();
    vector<int> sz(n);
    vector<int> par(n);
    function<void(int, int)> dfs = [&](int id, int fr) {
        sz[id] = 1; par[id] = fr;
        for (int to : G[id])if (to != fr) {
            dfs(to, id); sz[id] += sz[to];
        }
    }; dfs(0, -1);
    auto calc = [&](int a, int b) {
        if (par[a] == b) {
            return n - sz[a];
        }
        else {
            return sz[b];
        }
    };
    auto query = [&](int a, int b) {
        int d = lc.dist(a, b);
        if (d == 0)return n;
        if (d % 2)return 0;
        int m = lc.proc_d(a, b, d / 2);
        int res = n;
        int ma = lc.proc_d(m, a, 1);
        int mb = lc.proc_d(m, b, 1);
        res -= calc(m, ma);
        res -= calc(m, mb);
        return res;
    };
    rep(i, q) {
        int a, b; cin >> a >> b; a--; b--;
        cout << query(a, b) << "\n";
    }
}





signed main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    //cout << fixed << setprecision(15);
    init_f();
    //init();
    //while(true)
    //expr();
    //int t; cin >> t; rep(i, t)
    solve();
    return 0;
}

yukicoder

結果

テストケース

ソースコード