Submission #638631

#	Time	Username	Problem	Language	Result	Execution time	Memory
638631		browntoad	Let's Win the Election (JOI22_ho_t3)	C++14	10 / 100	1192 ms	8492 KiB

Main

#include <bits/stdc++.h>
#pragma GCC optimize ("Ofast", "unroll-loops")
using namespace std;
#define ll long long
#define int ll
#define FOR(i,a,b) for (int i = (a); i<(b); i++)
#define REP(i,n) FOR(i,0,n)
#define REP1(i,n) FOR(i,1,n+1)
#define RREP(i,n) for (int i=(n)-1; i>=0; i--)
#define f first
#define s second
#define pb push_back
#define ALL(x) x.begin(),x.end()
#define SZ(x) (int)(x.size())
#define SQ(x) (x)*(x)
#define pii pair<int, int>
#define pdd pair<double ,double>
#define pcc pair<char, char> 
#define endl '\n'
//#define TOAD
#ifdef TOAD
#define bug(x) cerr<<__LINE__<<": "<<#x<<" is "<<x<<endl
#define IOS()
#else
#define bug(...)
#define IOS() ios::sync_with_stdio(0), cin.tie(0), cout.tie(0)
#endif

const ll inf = 1ll<<60;
const int iinf=2147483647;
const ll mod = 1e9+7;
const ll maxn=505;
const double PI=acos(-1);

ll pw(ll x, ll p, ll m=mod){
    ll ret=1;
    while (p>0){
        if (p&1){
            ret*=x;
            ret%=m;
        }
        x*=x;
        x%=m;
        p>>=1;
    }
    return ret;
}

ll inv(ll a, ll m=mod){
    return pw(a,m-2);
}

//=======================================================================================

int n, k;
vector<pii> vc;
bool cmp(pii a, pii b){
    if (a.s==-1&&b.s==-1){
        return a.f<b.f;
    }
    if (a.s==-1||b.s==-1){
        return a.s>b.s;
    }
    return a.s<b.s;
}

long double dp[maxn][maxn], sf[maxn][maxn];
signed main (){
    IOS();
    cout<<fixed<<setprecision(15);
    cin>>n>>k;
    REP(i, n){
        int x, y; cin>>x>>y;
        vc.pb({x, y});
    }
    sort(ALL(vc), cmp);

    REP(i, maxn){
        REP(j, maxn){
            if (j==0) sf[i][j]=0;
            else sf[i][j]=inf;
        }
    }
    RREP(i, n){
        vector<int> cur;
        FOR(j, i, n){
            cur.pb(vc[j].f);
        }
        sort(ALL(cur));
        REP1(j, k){
            if (j>SZ(cur)) break;
            else sf[i][j]=sf[i][j-1]+cur[j-1];
        }
    }
    long double res=sf[0][k];
    REP1(t, k){
        REP(i, n){
            REP(j, t+1){
                dp[i][j]=inf;
            }
        }
        REP(i, n){
            if (i==0){
                dp[i][0]=(0.0+vc[i].f)/(t+1);
                if (vc[i].s!=-1) dp[i][1]=(0.0+vc[i].s);
                continue;
            }
            REP(j, t+1){
                if (j>i+1) break;
                if (j==0){
                    dp[i][0]=dp[i-1][0]+(0.0+vc[i].f)/(t+1);
                }
                else dp[i][j]=min(dp[i-1][j]+(0.0+vc[i].f)/(t+1), ((vc[i].s!=-1)?(dp[i-1][j-1]+(0.0+vc[i].s)/(j)):(0.0+inf)));
            }
        }
        REP(i, n){
            res=min(res, dp[i][t]+sf[i+1][k-t]/(t+1));
        }
        //res=min(res, dp[t-1][t]+(0.0+sf[t][k-t])/(t+1)); // 0 base
    }
    assert(res!=0);
    assert(res!=inf);
    cout<<res<<endl;

}

• Subtask 1: 5 / 5
• Subtask 2: 5 / 5
• Subtask 3: 0 / 11
• Subtask 4: 0 / 12
• Subtask 5: 0 / 33
• Subtask 6: 0 / 11
• Subtask 7: 0 / 23