Submission #535389

#	Time	Username	Problem	Language	Result	Execution time	Memory
535389		Killer2501	Let's Win the Election (JOI22_ho_t3)	C++14	100 / 100	178 ms	2444 KiB

Main

#include <bits/stdc++.h>
#define ll long long
#define ld long double
#define pb push_back
#define pll pair<ll, int>
#define pii pair<int, int>
#define fi first
#define se second
using namespace std;
const int N = 5e2+5;
const int M = 8;
const int mod = 998244353;
const int base = 350;
const int inf = 1e9;
int m, n, k, t, c[N],  d[N] ;
int ans, tong, b[N], a[N];
vector<int> adj[N];
string s;
int r, sz, ntime;
struct BIT
{
    int n;
    vector<int> fe;
    BIT(){}
    void init(int _n)
    {
        n = _n;
        fe.assign(n+1, 0);
    }
    void add(int id, int x)
    {
        ++id;
        for(; id <= n; id += id & -id)fe[id] += x;
    }
    int get(int id)
    {
        ++id;
        id = min(id, n);
        if(id <= 0)return 0;
        int total = 0;
        for(; id; id -= id & -id)total += fe[id];
        return total;
    }
    int get(int l, int r)
    {
        return get(r) - get(l-1);
    }
}bit[3];
void dfs(int u, int p = 0)
{
    int mx = 0;
    d[u] = 1;
    for(int v: adj[u])
    {
        if(v == p || b[v])continue;
        dfs(v, u);
        d[u] += d[v];
        mx = max(d[v], mx);
    }
    mx = max(mx, sz-d[u]);
    if(mx*2 <= sz)r = u;
}

pii p[N];
double dp[N][N];
bool cmp(const pii& x, const pii& y)
{
    if(x.se == y.se)return x.fi < y.fi;
    if(x.se == -1 || y.se == -1)return x.se > y.se;
    return x.se < y.se;
}
void add(double& x, double y)
{
    if(x > y)x = y;
}
void sol()
{
    cin >> n >> k;
    for(int i = 1; i <= n; i ++)cin >> p[i].fi >> p[i].se;
    sort(p+1, p+1+n, cmp);
    double res = inf;
    for(int i = 0; i <= k; i ++)
    {
        for(int j = i+1; j <= n; j ++)a[j-i] = p[j].fi;
        sort(a+1, a+n-i+1);
        for(int j = 1; j <= k-i; j ++)b[i] += a[j];
    }
    for(int x = 0; x <= k; x ++)
    {
        for(int j = 1; j <= x; j ++)dp[0][j] = inf;
        add(res, dp[0][x]+b[0]);
        for(int i = 1; i <= k; i ++)
        {
            for(int j = 0; j <= x; j ++)
            {
                dp[i][j] = inf;
                add(dp[i][j], dp[i-1][j] + p[i].fi*1.0/(x+1));
                if(j && p[i].se != -1)add(dp[i][j], dp[i-1][j-1] + p[i].se*1.0/j);
            }
            add(res, dp[i][x]+b[i]*1.0/(x+1));
        }
    }
    cout << fixed << setprecision(5) << res;
}
int main()
{
    cin.tie(0);
    cout.tie(0);
    ios_base::sync_with_stdio(0);
    #define task "test"
    if(fopen(task".inp", "r"))
	{
		freopen(task".inp", "r", stdin);
		freopen(task".out", "w", stdout);
	}
    int test = 1;
    //cin >> test;
    while(test -- > 0)sol();
    return 0;
}

Compilation message (stderr)

Main.cpp: In function 'int main()':
Main.cpp:113:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  113 |   freopen(task".inp", "r", stdin);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:114:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  114 |   freopen(task".out", "w", stdout);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

• 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