Kanade selected n courses in the university. The academic credit of the i-th course is s[i] and the score of the i-th course is c[i].

At the university where she attended, the final score of her is 

Now she can delete at most k courses and she want to know what the highest final score that can get.

The first line has two positive integers n,k

The second line has n positive integers s[i]

The third line has n positive integers c[i]

Output the highest final score, your answer is correct if and only if the absolute error with the standard answer is no more than 10

3 1

1 2 3

3 2 1

2.33333333333

1≤ n≤ 10

0≤ k < n

1≤ s[i],c[i] ≤ 10

#include <map>

#include <set>

#include <stack>

#include <cmath>

#include <queue>

#include <cstdio>

#include <vector>

#include <string>

#include <cstring>

#include <iomanip>

#include <iostream>

#include <algorithm>

#define ls (r<<1)

#define rs (r<<1|1)

#define debug(a) cout << #a << " " << a << endl

using namespace std;

typedef long long ll;

const ll maxn = 1e5 + 10;

const ll mod = 1e9 + 7;

ll s[maxn], c[maxn], n, k;

double le, ri, t[maxn];

bool check( double x ) {

    for( ll i = 1; i <= n; i ++ ) {

        t[i] = s[i]*(c[i]-x);

    }

    sort( t+1, t+n+1 );

    double tmp = 0.0;

    for( ll i = k+1; i <= n; i ++ ) {

        tmp += t[i];

    }

    return tmp>0;

}

int main() {

    ios::sync_with_stdio(0),cin.tie(0),cout.tie(0);

    cin >> n >> k;

    for( ll i = 1; i <= n; i ++ ) {

        cin >> s[i];

    }

    for( ll i = 1; i <= n; i ++ ) {

        cin >> c[i];

        ri = max( ri, (double)c[i] );

    }

    double mid;

    while( ri-le > 1e-6 ) {

        mid = (le+ri)/2;

        //debug(mid);

        if( check(mid) ) {

            le = mid;

        } else {

            ri = mid;

        }

    }

    printf("%.10lf\n",mid);

    return 0;

}