Submission #907602

#	Time	Username	Problem	Language	Result	Execution time	Memory
907602		vjudge1	Let's Win the Election (JOI22_ho_t3)	C++17	0 / 100	489 ms	1048576 KiB

Main

#pragma GCC target ("avx2")
#pragma GCC optimize ("O3")
#pragma GCC optimize ("unroll-loops")

#include<bits/stdc++.h>
#include<math.h>
using namespace std;

typedef long long int ll;
typedef long double ld;
typedef pair<ll, ll> pl;
typedef vector<ll> vl;
#define FD(i, r, l) for(ll i = r; i > (l); --i)

#define K first
#define V second
#define G(x) ll x; cin >> x;
#define GD(x) ld x; cin >> x;
#define GS(s) string s; cin >> s;
#define EX(x) { cout << x << '\n'; exit(0); }
#define A(a) (a).begin(), (a).end()
#define F(i, l, r) for (ll i = l; i < (r); ++i)

#define NN 510
#define M 1000000007 // 998244353

vector<pl> votes;
ll n, k;
ll take;

ld dp[NN][NN][NN]; // 

ld rec(ll i, ll bs, ll vots) {
    if (i == n) return vots + bs >= k and bs >= take ? 0: 1e18;
    auto &DP = dp[i][bs][vots];
    if (DP != DP) {
        DP = 1e18;
        DP = min(DP, rec(i+1, bs, vots)); 
        DP = min(DP, rec(i+1, bs, vots+1) + ld(votes[i].V)/(1 + take)); 
        if (~votes[i].K) DP = min(DP, rec(i+1, bs+1, vots) + ld(votes[i].K)/(1 + bs)); 
    }
    return DP;
}
ld cache[510];

ld q(ll i) {
    take = i;
    if (i < 0 || i > n) return 1e18;
    if (cache[i] == cache[i]) return cache[i];
    memset(dp, -1, sizeof dp);
    return cache[i] = rec(0, 0, 0);
}

int main(){
//    freopen("a.in", "r", stdin);
//    freopen("a.out", "w", stdout);

    ios_base::sync_with_stdio(false); cin.tie(0);
    cout << fixed << setprecision(20);
    cin >> n >> k;
    votes.resize(n);
    for (auto &[b, a]: votes) {
        cin >> a >> b;
    }
    memset(cache, -1, sizeof cache);
    sort(A(votes));
    ld ans = 1e18; 

    ll l = -1, r = n;
    while (l+1<r) {
        ll mid = (l+r)/2;
        if (q(mid) < q(mid+1)) l = mid;
        else r = mid;
    }
    F(th, l-2, l+3) ans = min(ans, q(l));

    cout << ans << endl;

}

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