Submission #534685

#	Time	Username	Problem	Language	Result	Execution time	Memory
534685		browntoad	Let's Win the Election (JOI22_ho_t3)	C++14	66 / 100	143 ms	18788 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 pdd pair<double ,double>
#define pii pair<int, int>
#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=105;
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);
}

//=======================================================================================
double dp[maxn][maxn][maxn];
bool cmp(pdd x, pdd y){
    if (x.s==y.s&&x.s==-1){
        return x.f<y.f;
    }
    if (x.s==-1||y.s==-1){
        return x.s>y.s;
    }
    return x.s<y.s;
}
signed main (){
    IOS();
    cout<<fixed<<setprecision(9);
    int n, K; cin>>n>>K;
    vector<pdd> vc(n+1), ov(n);
    REP1(i,n){
        cin>>vc[i].f>>vc[i].s;
        ov[i-1]=vc[i];
    }
    sort(ALL(vc), cmp);
    bool ok=1;
    REP1(i,n){
        if (vc[i].s==-1||vc[i].f==vc[i].s){
            
        }
        else ok=0;
    }
    if (ok){
        int k=K;
        int pos=0;
        double res=inf;
        sort(ALL(ov), cmp);
        if (ov[0].s==ov[n-1].s&&ov[0].s==-1){
            int res=0;
            REP(i,k){
                res+=ov[i].f;
            }
            cout<<res<<endl;
            return 0;
        }
        REP(i,n){
            if (ov[i].s==-1){
                break;
            }
            pos++;
        }
        
        REP(i,min(k+1, pos+1)){
            //cout<<i<<endl;
            double cur=0;
            REP(j,i){
                //cout<<j<<endl;
                //cout<<vc[i].f/(j+1)<<endl;
                cur+=ov[j].f/(0.0+j+1);
                //cout<<cur<<endl;
            }
            //cout<<cur<<endl;
            if (cur==inf||pos+(k-i)-1>=n) continue;
            REP(j, k-i){
                //cout<<j+pos<<endl;
                cur+=ov[pos+j].f/(0.0+i+1);
                //cout<<cur<<endl;
            }
            res=min(res, cur);
        }
        cout<<res<<endl;
        return 0;
    }
    double ans=inf;
    REP(k, K+1){
        /*if (k==0){
            vector<double> cur;
            REP1(i,n) cur.pb(vc[i].f);
            sort(ALL(cur));
            REP1(i, K){
                ans+=cur[i];
            }
            continue;
        }
        */
        /*dp[1][1][1]=vc[1].s;
        dp[1][1][0]=vc[1].f/k;
        dp[1][0][0]=0;
        */
        REP(i,maxn){
            REP(j,maxn){
                REP(l,maxn){
                    dp[i][j][l]=inf;
                }
            }
        }
        dp[1][1][1]=vc[1].s;
        dp[1][1][0]=vc[1].f/(k+1);
        dp[1][0][0]=0;
        FOR(i,2,n+1){
            dp[i][0][0]=0.0;
            FOR(j, 1, i+1){
                dp[i][j][0]=min(dp[i-1][j-1][0]+vc[i].f/(k+1), dp[i-1][j][0]);
                FOR(l, 1, j+1){
                    if (vc[i].s==-1){
                        dp[i][j][l]=min(dp[i-1][j-1][l]+vc[i].f/(k+1), dp[i-1][j][l]);
                    }
                    else dp[i][j][l]=min({dp[i-1][j-1][l-1]+vc[i].s/l, dp[i-1][j-1][l]+vc[i].f/(k+1), dp[i-1][j][l]});
                }
            }
        }
        ans=min(ans, dp[n][K][k]);
    }
    cout<<ans<<endl;
}

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