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ID题目提交者结果用时内存语言文件大小提交时间测评时间
#690794#4925. Adjacent PairsMher7770 0ms0kbC++206.6kb2024-10-31 03:56:332024-10-31 03:56:33

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你现在查看的是最新测评结果

  • [2024-10-31 03:56:33]
  • 评测
  • 测评结果:0
  • 用时:0ms
  • 内存:0kb
  • [2024-10-31 03:56:33]
  • 提交

answer

#define _CRT_SECURE_NO_WARNINGS
#include <iostream>
#include <iomanip>
#include <array>
#include <string>
#include <algorithm>
#include <cmath>
#include <set>
#include <map>
#include <unordered_set>
#include <unordered_map>
#include <vector>
#include <stack>
#include <queue>
#include <deque>
#include <bitset>
#include <list>
#include <iterator>
#include <numeric>
#include <complex>
#include <utility>
#include <random>
#include <cassert>
#include <fstream>
using namespace std;
mt19937 rnd(time(nullptr));

/* -------------------- Typedefs -------------------- */

typedef int itn;
typedef long long ll;
typedef unsigned long long ull;
typedef double db;
typedef float fl;
typedef long double ld;

/* -------------------- Usings -------------------- */

using vi = vector<int>;
using vll = vector<ll>;
using mii = map<int, int>;
using mll = map<ll, ll>;
using pii = pair<int, int>;
using pll = pair<ll, ll>;

/* -------------------- Defines -------------------- */

#define ff first
#define ss second
#define pub push_back
#define pob pop_back
#define puf push_front
#define pof pop_front
#define mpr make_pair
#define yes cout<<"Yes\n"
#define no cout<<"No\n"
#define all(x) (x).begin(), (x).end()
#define USACO freopen("feast.in", "r", stdin); freopen("feast.out", "w", stdout);

/* -------------------- Constants -------------------- */

const int dx[8] = { -1, 0, 1, 0, -1, -1, 1, 1 };
const int dy[8] = { 0, -1, 0, 1, -1, 1, -1, 1 };
const int MAX = int(1e9 + 5);
const ll MAXL = ll(1e18) + 5ll;
const ll MOD = ll(1000000007);
const ll MOD2 = ll(998244353);

/* -------------------- Functions -------------------- */

void fastio() {
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
}

void precision(int x) {
    cout.setf(ios::fixed | ios::showpoint);
    cout.precision(x);
}

ll gcd(ll a, ll b) {
    if (a == 0 || b == 0) return(max(a, b));
    while (b) {
        a %= b;
        swap(a, b);
    }
    return a;
}

ll lcm(ll a, ll b) {
    return a / gcd(a, b) * b;
}

ll range_sum(ll a, ll b) {
    if (a > b) return 0ll;
    ll dif = a - 1, cnt = b - a + 1;
    ll ans = ((b - a + 1) * (b - a + 2)) / 2;
    ans += ((b - a + 1) * dif);
    return ans;
}

string dec_to_bin(ll a) {
    string s = "";
    for (ll i = a; i > 0; ) {
        ll k = i % 2;
        i /= 2;
        char c = k + 48;
        s += c;
    }
    if (a == 0) {
        s = "0";
    }
    reverse(all(s));
    return s;
}

ll bin_to_dec(string s) {
    ll num = 0;
    for (int i = 0; i < s.size(); i++) {
        num *= 2ll;
        num += (s[i] - '0');
    }
    return num;
}

ll factorial_by_mod(ll n, ll mod) {
    ll ans = 1;
    ll num;
    for (ll i = 1; i <= n; ++i) {
        num = i % mod;
        ans *= num;
        ans %= mod;
    }
    return ans;
}

bool isPrime(ll a) {
    if (a == 1) return false;
    for (ll i = 2; i * i <= a; i++) {
        if (a % i == 0) return false;
    }
    return true;
}

ll binpow(ll a, ll b) {
    if (!a) return 0;
    ll ans = 1;
    while (b) {
        if (b & 1) {
            ans *= a;
        }
        b >>= 1;
        a *= a;
    }
    return ans;
}

ll binpow_by_mod(ll a, ll b, ll mod) {
    if (!a) return 0;
    ll ans = 1;
    while (b) {
        if (b & 1) {
            ans *= a;
            ans %= mod;
        }
        b >>= 1;
        a *= a;
        a %= mod;
    }
    return ans;
}

/* -------------------- Solution -------------------- */

const int N = 200005;
set<pii> adj[N];
int a[N], cnt[N][2], used[N];
int n, ans;

void clearr() {
    for (int i = 1; i <= n; ++i) {
        adj[a[i]].clear();
        cnt[a[i]][0] = cnt[a[i]][1] = used[a[i]] = 0;
    }
}

void slv() {
    cin >> n;
    ans = n;
    set<int> num_set;
    for (int i = 1; i <= n; ++i) {
        cin >> a[i];
        if (i % 2) num_set.insert(a[i]);
        ++cnt[a[i]][i % 2];
        ans = min(ans, n - cnt[a[i]][i % 2]);
    }
    set<pii> st;
    for (int i = 1; i <= n; ++i) {
        if (i % 2) {
            if (i != n) {
                st.insert({ a[i + 1],a[i] });
                adj[a[i]].insert({ a[i + 1], 1 });
            }
            if (i != 1) {
                adj[a[i]].insert({ a[i - 1], 1 });
            }
        }
        else {
            if (i != n) {
                adj[a[i]].insert({ a[i + 1],0 });
                st.insert({ a[i],a[i + 1] });
            } 
            adj[a[i]].insert({ a[i - 1],0 });
        }
    }
    map<pii, pair<int, int>> mp_even, mp_odd;
    for (int i = 1; i < n; ++i) {
        pii opt = { a[i],a[i + 1] };
        int len = 2, ind = i + 2;
        while (ind <= n) {
            if (a[ind] == opt.ff) {
                ++len;
                swap(opt.ff, opt.ss);
                ++ind;
            }
            else {
                break;
            }
        }
        if (i % 2) {
            mp_odd[{a[i], a[i + 1]}].ff += (len / 2) * 2 + len / 2 + len % 2;
            mp_odd[{a[i], a[i + 1]}].ss += len;
        }
        else {
            mp_even[{a[i], a[i + 1]}].ff += (len / 2) * 2 + len / 2 + len % 2;
            mp_even[{a[i], a[i + 1]}].ss += len;
        }
        i = ind - 2;
    }
    for (auto elem : st) {
        int num1 = elem.ff, num2 = elem.ss;
        int answ = n - cnt[num1][1] - cnt[num2][0] - mp_even[elem].ss - mp_odd[{num2, num1}].ss;
        answ += mp_even[elem].ff;
        answ += mp_odd[{num2, num1}].ff;
        ans = min(ans, answ);
    }
    multiset<int> mst, del;
    mst.insert(0);
    for (int i = 2; i <= n; i += 2) {
        if (used[a[i]]) continue;
        used[a[i]] = 1;
        mst.insert(cnt[a[i]][0]);
    }
    for (auto elem : num_set) {
        del.clear();
        if (used[elem]) {
            mst.erase(mst.find(cnt[elem][0]));
            del.insert(cnt[elem][0]);
        }
        for (auto to : adj[elem]) {
            if ((to.ss % 2 && st.find({ elem,to.ff }) != st.end()) || (to.ss % 2 == 0 && st.find({ elem,to.ff }) != st.end())) {
                del.insert(cnt[to.ff][0]);
                mst.erase(mst.find(cnt[to.ff][0]));
            }
        }
        int answ = n - cnt[elem][1] - *mst.rbegin();
        ans = min(ans, answ);
        for (auto u : del) {
            mst.insert(u);
        }
    }
    cout << ans << '\n';
    clearr();
}

/*
1
10
5 1 5 6 10 5 7 10 1 10
*/

void cs() {
    int tstc = 1;
    cin >> tstc;
    while (tstc--) {
        slv();
    }
}

void precalc() {
    return;
}

int main() {
    fastio();
    precalc();
    //precision(0);
    cs();
    return 0;
}

详细

Subtask #1:

score: 0
Time Limit Exceeded

Test #1:

score: 0
Time Limit Exceeded

input:

2
5
4 5 2 4 5
2
1 2

output:


result:


Subtask #2:

score: 0
Skipped

Dependency #1:

0%

Subtask #3:

score: 0
Skipped

Dependency #1:

0%

Subtask #4:

score: 0
Skipped

Dependency #1:

0%