Submission #702192

#	Time	Username	Problem	Language	Result	Execution time	Memory
702192		nicky4321	Group Photo (JOI21_ho_t3)	C++14	44 / 100	5035 ms	5212 KiB

Main

//#pragma GCC optimize("Ofast,no-stack-protector")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,avx2,tune=native")
#include<bits/stdc++.h>
#define ll long long
#define ld long double
#define F first
#define S second
#define PB push_back
#define pii pair<int, int>
#define pll pair<ll, ll>
#define pdd pair<double, double>
#define ALL(x) x.begin(), x.end()
#define SZ(x) (int)x.size()
#define vi vector<int>
#define vl vector<ll>
#define CASE int t;cin>>t;for(int ca=1;ca<=t;ca++)
#define IOS ios_base::sync_with_stdio(false); cin.tie(0);
using namespace std;
const int MAX = 5007, MOD = 1e9 + 7;
ll a[MAX], bit[MAX], dp[MAX][MAX], ans[MAX];

void upd(int x, int v){
    while(x < MAX){
        bit[x] += v;
        x += x & -x;
    }
}

int qry(int x){
    int res = 0;
    while(x){
        res += bit[x];
        x -= x & -x;
    }
    return res;
}

void solve(){
    int n;
    cin >> n;
    for(int i = 1;i <= n;i++){
        cin >> a[i];
        ans[i] = 2e18;
    }
    for(int i = 1;i <= n;i++){
        for(int j = 1;j <= i;j++){
            for(int k = n;k >= 1;k--){
                if(i < a[k]){
                    dp[j][i] += qry(n);
                    upd(n + 1, 1);
                }else if(j <= a[k] && a[k] <= i){
                    int pos = i - a[k] + j + 1;
                    dp[j][i] += qry(pos - 1);
                    upd(pos, 1);
                }
            }
            for(int k = 1;k <= n;k++){
                if(i < a[k])
                    upd(n + 1, -1);
                else if(j <= a[k] && a[k] <= i){
                    int pos = i - a[k] + j + 1;
                    upd(pos, -1);
                }
            }
        }
    }
    for(int i = 0;i < n;i++){
        for(int j = 1;j <= n;j++)
            ans[j] = min(ans[j], ans[i] + dp[i + 1][j]);
    }
    cout << ans[n] << '\n';
}

int main(){
    IOS
	// CASE
	    solve();
    return 0;
}

• Subtask 1: 5 / 5
• Subtask 2: 7 / 7
• Subtask 3: 32 / 32
• Subtask 4: 0 / 20
• Subtask 5: 0 / 36