Submission #758153

#	Time	Username	Problem	Language	Result	Execution time	Memory
758153		PixelCat	Rope (JOI17_rope)	C++14	55 / 100	2555 ms	127584 KiB

rope

#include <bits/stdc++.h>
#define For(i, a, b) for(int i = a; i <= b; i++)
#define Forr(i, a, b) for(int i = a; i >= b; i--)
#define F first
#define S second
#define all(x) x.begin(), x.end()
#define sz(x) ((int)x.size())
#define eb emplace_back
#define int LL
#define INF (int)(1e18)
using namespace std;
using LL = long long;
using pii = pair<int, int>;

void chmin(int &x, int a) {
    x = min(x, a);
}
void chmax(int &x, int a) {
    x = max(x, a);
}

const int MAXN = 1000010;

int ans[MAXN];
int cnt1[MAXN];

struct Ayaya {
    int a[MAXN];
    multiset<int> st;
    void init(int n) {
        memset(a, 0, sizeof(a));
        st.clear();
        For(i, 1, n) st.insert(0);
    }
    void upd(int i, int x) {
        st.erase(st.find(a[i]));
        a[i] = x;
        st.insert(a[i]);
    }
    void add(int i, int x) {
        upd(i, a[i] + x);
    }
    int min() {
        return *st.begin();
    }
} aya;

void solve(int n, int m, vector<pii> v2, vector<int> v1) {
    memset(cnt1, 0, sizeof(cnt1));
    map<pii, int> cnt2;
    for(auto &i:v2) {
        cnt1[i.F]++;
        cnt1[i.S]++;
        cnt2[i]++;
        cnt2[pii(i.S, i.F)]++;
    }
    vector<vector<pii>> vv(m + 1, vector<pii>());
    for(auto &i:cnt2) {
        vv[i.F.F].eb(i.F.S, i.S);
    }
    aya.init(m);
    For(c2, 1, m) aya.upd(c2, n - cnt1[c2]);
    // 2, 2
    // 2 1, 1 3, 3 2, 1 1
    // 2 2, 1 1, 3 3, 2 1, 1 2
    For(c1, 1, m) {
        int add = 0;
        for(auto &p:vv[c1]) {
            aya.add(p.F, p.S);
        }
        for(auto &i:v1) {
            aya.add(i, -1);
            if(i == c1) add--;
        }
        aya.add(c1, INF);
        chmin(ans[c1], aya.min() - cnt1[c1] + add);
        // cout << aya.min() << ", " << add << ", " << (aya.min() - cnt1[c1] + add) << ": ";
        // For(c2, 1, m) cout << (aya.a[c2] >= INF ? -1 : aya.a[c2]) << " \n"[c2 == m];
        aya.add(c1, -INF);
        for(auto &i:v1) aya.add(i, 1);
        for(auto &p:vv[c1]) aya.add(p.F, -p.S);
        // For(c2, c1 + 1, m) {
        //     int cost = n - cnt1[c1] - cnt1[c2];
        //     if(cnt2.count(pii(c1, c2))) cost += cnt2[pii(c1, c2)];
        //     for(auto &i:v1) {
        //         cost -= max(i == c1, i == c2);
        //     }
        //     chmin(ans[c1], cost);
        //     chmin(ans[c2], cost);
        // }
        int cost = n - cnt1[c1];
        for(auto &i:v1) cost -= (i == c1);
        chmin(ans[c1], cost);
    }
}

int32_t main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    // =^-w-^=
    int n, m; cin >> n >> m;
    vector<int> a(n);
    for(auto &i:a) cin >> i;

    For(i, 1, m) {
        ans[i] = INF;
    }

    if(n % 2) {
        For(_, 0, 1) {
            vector<pii> v2;
            for(int i = 1; i < n; i += 2) {
                v2.eb(pii(a[i - 1], a[i]));
            }
            solve(n, m, v2, { a.back() });
            reverse(all(a));
        }
    } else {
        vector<pii> v2;
        for(int i = 1; i < n; i += 2) {
            v2.eb(pii(a[i - 1], a[i]));
        }
        solve(n, m, v2, {});

        v2.clear();
        for(int i = 2; i < n; i += 2) {
            v2.eb(pii(a[i - 1], a[i]));
        }
        solve(n, m, v2, { a.front(), a.back() });
    }

    For(i, 1, m) cout << ans[i] << "\n";
    return 0;
}

• Subtask 1: 15 / 15
• Subtask 2: 30 / 30
• Subtask 3: 10 / 10
• Subtask 4: 0 / 25
• Subtask 5: 0 / 20