#include <iostream>
#include <math.h>
#include <vector>
#include <array>
#include <algorithm>
#include <queue>
#include <numeric>
#include <map>
#include <set>

using namespace std;
#define int long long
#define FOR(i, a, b) for(int i=(a);i<(b);i++)
#define RFOR(i, a, b) for(int i=(b-1);i>=(a);i--)
#define REP(i, n) for(int i=0; i<(n); i++)
#define RREP(i, n) for(int i=(n-1); i>=0; i--)
#define ALL(a) (a).begin(),(a).end()
#define UNIQUE_SORT(l) sort(ALL(l)); l.erase(unique(ALL(l)), l.end());
#define CONTAIN(a, b) find(ALL(a), (b)) != (a).end()
#define array2(type, x, y) array<array<type, y>, x>
#define vector2(type) vector<vector<type> >
#define out(...) printf(__VA_ARGS__)

typedef pair<int, int> pos;
int pos::*x = &pos::first;
int pos::*y = &pos::second;

int dxy[] = {0, 1, 0, -1, 0};

/*================================*/

int N;
vector<int> A, B;

bool shuff(const int& riLeft, const int& riRight) {
    return rand() % 2;
};

signed main()
{
    cin >> N;
    A = vector<int>(N);
    REP(i,N) cin >> A[i];
    B = vector<int>(N);
    REP(i,N) cin >> B[i];


    int trynum = 100000;
    int ret = 0;
    REP(i,trynum) {
        int win = 0;
        ALL(A);
        //sort(ALL(A), shuff);
        //sort(ALL(B), shuff);
        REP(j,N) {
            if (A[j] > B[j]) win++;
            else if (A[j] < B[j]) win--;
        }
        ret += (win > 0);
    }

    printf("%.7f\n", 1.0 * ret / trynum);

    return 0;
}