Submission #814718

#	Time	Username	Problem	Language	Result	Execution time	Memory
814718		Cookie	Growing Vegetables is Fun 4 (JOI21_ho_t1)	C++14	100 / 100	31 ms	8160 KiB

Main

#include<bits/stdc++.h>
#include<fstream>
using namespace std;
ifstream fin("FEEDING.INP");
ofstream fout("FEEDING.OUT");
#define sz(a) (int)a.size()
#define ll long long
#define pb push_back
#define forr(i, a, b) for(int i = a; i < b; i++)
#define dorr(i, a, b) for(int i = a; i >= b; i--)
#define ld long double
#define vt vector
#include<fstream>
#define fi first
#define se second
#define pll pair<ll, ll>
#define pii pair<int, int>
const ld PI = 3.14159265359;
using u128 = __uint128_t;
//const int x[4] = {1, -1, 0, 0};
// int y[4] = {0, 0, 1, -1};
const ll mod = 1e15 + 7, inf = 1e16;
const int mxn = 2e5 + 5;
int n, q;
ll a[mxn + 1], pat[mxn + 1], sat[mxn + 1], pneed[mxn + 1], sneed[mxn + 1];
signed main()
{
     ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
    cin >> n;
    for(int i = 1; i <= n; i++)cin >> a[i];
    pat[1] = a[1];
    for(int i = 2; i <= n; i++){
        pat[i] = max(pat[i - 1] + 1, a[i] + pneed[i - 1]);
        pneed[i] = pneed[i - 1] + (pat[i] - a[i] - pneed[i - 1]);
    }
    sat[n] = a[n];
    for(int i = n - 1; i >= 1; i--){
        sat[i] = max(sat[i + 1] + 1, a[i] + sneed[i + 1]);
        sneed[i] = sneed[i + 1] + (sat[i] - a[i] - sneed[i + 1]);
    }
    ll ans = inf;
    for(int i = 1; i <= n; i++){
        
        ll need = max(pneed[i - 1], sneed[i + 1]);
        ///cout << pneed[i - 1] << " " << sneed[i + 1] << " ";
        a[i] += need;
       
        ll v1 = pat[i - 1], v2 = sat[i + 1];
        //cout << v1 << " " << v2 << " " << a[i] << " " << need << " ";
        if(v1 >= a[i] && v2 >= a[i]){
            need += max(v1 + 1, v2 + 1) - a[i];
        }else if(v1 >= a[i]){
            ll more = v1 + 1 - a[i];
            need += more;
        }else if(v2 >= a[i]){
            ll more = v2 + 1 - a[i];
            need += more;
        }
        //cout << need << "\n";
        ans = min(ans, need);
    }
    cout << ans;
    return(0);
}

• Subtask 1: 40 / 40
• Subtask 2: 60 / 60