Submission #529570

#	Time	Username	Problem	Language	Result	Execution time	Memory
529570		wiwiho	Let's Win the Election (JOI22_ho_t3)	C++14	100 / 100	1743 ms	4572 KiB

Main

#include <bits/stdc++.h>
#include <bits/extc++.h>

#define StarBurstStream ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
#define iter(a) a.begin(), a.end()
#define riter(a) a.rbegin(), a.rend()
#define lsort(a) sort(iter(a))
#define gsort(a) sort(riter(a))
#define pb(a) push_back(a)
#define eb(a) emplace_back(a)
#define pf(a) push_front(a)
#define ef(a) emplace_front(a)
#define pob pop_back()
#define pof pop_front()
#define mp(a, b) make_pair(a, b)
#define F first
#define S second
#define mt make_tuple
#define gt(t, i) get<i>(t)
#define tomax(a, b) ((a) = max((a), (b)))
#define tomin(a, b) ((a) = min((a), (b)))
#define topos(a) ((a) = (((a) % MOD + MOD) % MOD))
#define uni(a) a.resize(unique(iter(a)) - a.begin())
#define printv(a, b) {bool pvaspace=false; \
for(auto pva : a){ \
    if(pvaspace) b << " "; pvaspace=true;\
    b << pva;\
}\
b << "\n";}

using namespace std;
using namespace __gnu_pbds;

typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;

using pii = pair<int, int>;
using pll = pair<ll, ll>;
using pdd = pair<ld, ld>;
using tiii = tuple<int, int, int>;

const ll MOD = 1000000007;
const ll MAX = 2147483647;

template<typename A, typename B>
ostream& operator<<(ostream& o, pair<A, B> p){
    return o << '(' << p.F << ',' << p.S << ')';
}

ll ifloor(ll a, ll b){
    if(b < 0) a *= -1, b *= -1;
    if(a < 0) return (a - b + 1) / b;
    else return a / b;
}

ll iceil(ll a, ll b){
    if(b < 0) a *= -1, b *= -1;
    if(a > 0) return (a + b - 1) / b;
    else return a / b;
}

int n, K;
vector<int> a, b;

ld calc(int cnt){
    //cerr << "calc " << cnt << "\n";

    vector<vector<ld>> dp(cnt + 1, vector<ld>(n + 1, 1e87));
    dp[0][0] = 0;
    
    for(int i = 1; i <= n; i++){
        
        for(int j = K; j >= 1; j--){
            dp[cnt][j] = min(dp[cnt][j], dp[cnt][j - 1] + (ld)a[i] / (cnt + 1));
        }

        for(int j = cnt; j >= 0; j--){
            if(j != cnt) dp[j][i] = min(dp[j][i], dp[j][i - 1] + (ld)a[i] / (cnt + 1));
            if(j && b[i] != -1) dp[j][i] = min(dp[j][i], dp[j - 1][i - 1] + (ld)b[i] / j);
        }

        //cerr << "dp " << i << "\n";
        //for(int j = 0; j <= cnt; j++) printv(dp[j], cerr);
    }

    //cerr << "calc ok " << dp[cnt][K] << "\n";
    return dp[cnt][K];
}

int main(){
    StarBurstStream

    cin >> n >> K;
    a.resize(n + 1);
    b.resize(n + 1);

    vector<pii> tmp(n + 1);
    for(int i = 1; i <= n; i++) cin >> tmp[i].F >> tmp[i].S;

    sort(tmp.begin() + 1, tmp.end(), [&](pii a, pii b){
        if(a.S == b.S) return false;
        if(a.S == -1) return false;
        if(b.S == -1) return true;
        return a.S < b.S; 
    });
    for(int i = 1; i <= n; i++) tie(a[i], b[i]) = tmp[i];

    ld ans = 1e87;
    for(int i = 0; i <= K; i++) ans = min(ans, calc(i));
    
    cout << fixed << setprecision(20) << ans << "\n";

    return 0;
}

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