제출 #1200571

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1200571		InvMOD	즐거운 채소 기르기 (JOI14_growing)	C++17	30 / 100	9 ms	1732 KiB

growing

#include<bits/stdc++.h>

using namespace std;

#define fi first
#define se second
#define pb push_back
#define eb emplace_back

#define vi vector<int>
#define pi pair<int,int>
#define sz(v) (int)(v).size()
#define all(v) (v).begin(), (v).end()
#define compact(v) (v).erase(unique(all(v)), (v).end())

template<class T> using upq = priority_queue<T, vector<T>, greater<T>>;
template<class T> int lwrbound(const vector<T>& a, const T& b, const int s = 0){return int(lower_bound(s + all(a), b) - a.begin());}
template<class T> int uprbound(const vector<T>& a, const T& b, const int s = 0){return int(upper_bound(s + all(a), b) - a.begin());}

#define FOR(i, a, b) for(int i = (a); i <= (b); i++)
#define ROF(i, a, b) for(int i = (a); i >= (b); i--)
#define sumof(x) accumulate(all(x), 0ll)
#define dbg(x) "[" << #x " = " << (x) << "]"
#define el "\n"

using ll = long long;
using ld = long double;

template<class T> bool ckmx(T& a, const T b){return (a < b ? a = b, true : false);}
template<class T> bool ckmn(T& a, const T b){return (a > b ? a = b, true : false);}

const int N = 2e5 + 5;
const int MOD = 1e9 + 7;
const ll INF = numeric_limits<ll>::max() / 8;

struct BIT{
    vector<int> bit;

    BIT(int n = 0): bit(n + 1) {}

    void update(int p, int val){
        for(; p < sz(bit); p += p & -p){
            bit[p] += val;
        }
    }

    int get(int p){
        int ans = 0;
        for(; p > 0; p -= p & -p){
            ans += bit[p];
        }
        return ans;
    }

    int query(int l, int r){
        return get(r) - get(l - 1);
    }
};

void Main()
{
    int n; cin >> n;

    vi a(n + 1); FOR(i, 1, n) cin >> a[i];

    vi comp; FOR(i, 1, n) comp.eb(a[i]);

    comp.eb(-1); sort(all(comp)), compact(comp);
    FOR(i, 1, n) a[i] = lwrbound(comp, a[i]);

    vector<ll> pref(n + 2), suf(n + 2); BIT bit(sz(comp));
    FOR(i, 1, n){
        pref[i] = pref[i - 1] + bit.query(a[i] + 1, sz(comp));
        bit.update(a[i], 1);
    }

    bit = BIT(sz(comp));
    ROF(i, n, 1){
        suf[i] = suf[i + 1] + bit.query(a[i] + 1, sz(comp));
        bit.update(a[i], 1);
    }

    ll ans = INF;
    FOR(i, 0, n){
        ckmn(ans, pref[i] + suf[i + 1]);
    }

    cout << ans << el;
}

int32_t main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);

    #define name "InvMOD"
    if(fopen(name".INP", "r")){
        freopen(name".INP", "r", stdin);
        freopen(name".OUT", "w", stdout);
    }

    int t = 1; while(t--) Main();
    return 0;
}

컴파일 시 표준 에러 (stderr) 메시지

growing.cpp: In function 'int32_t main()':
growing.cpp:98:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   98 |         freopen(name".INP", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
growing.cpp:99:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   99 |         freopen(name".OUT", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 20 / 20
• Subtask 3: 0 / 15
• Subtask 4: 0 / 55