#include <bits/stdc++.h>
using namespace std;
typedef pair<int, int> pii;
typedef long long ll;
const int inf=2e9, MX=300010;
struct edge{
ll x=1, y=0;
bool operator > (const edge &e) const {
return y*e.x>e.y*x;
}
bool operator == (const edge &e) const {
return y*e.x==e.y*x;
}
};
struct node1{
int idx; edge e;
bool operator < (const node1 &nd) const {
return idx<nd.idx;
}
};
struct node2{
int idx; edge e;
bool operator < (const node2 &nd) const {
return nd.e>e || (e==nd.e && idx<nd.idx);
}
bool operator==(const node2 &nd) const {
return !(*this < nd) && !(nd < *this);
}
};
set<node1> S1;
struct pq {
priority_queue<node2> pq1, pq2;
void insert(node2 x) {
pq1.push(x);
}
void erase(node2 x) {
pq2.push(x);
while (!pq2.empty() && pq1.top() == pq2.top()) {
pq1.pop();
pq2.pop();
}
}
node2 get() const {
return pq1.top();
}
} S2;
int n;
ll X[MX], Y[MX];
ll c;
int gcd(int x, int y){
if(y==0) return x;
return gcd(y,x%y);
}
ll area(int l, int r){
return (X[r]-X[l])*(Y[l]+Y[r]);
}
int main(){
scanf("%d%lld", &n, &c);
c*=2;
for(int i=1; i<=n; i++) scanf("%lld", &X[i]);
for(int i=1; i<=n; i++) scanf("%lld", &Y[i]);
for(int i=1; i<n; i++){
edge e;
e.x=X[i+1]-X[i];
e.y=Y[i+1]-Y[i];
S1.insert({i,e});
S2.insert({i,e});
}
while(true){
node2 a=S2.get();
int i=a.idx; edge e=a.e;
if(i==1) break;
node1 b=*prev(S1.find({i,e}));
int j=b.idx; edge f=b.e;
int k=n;
auto it=S1.find({i,e});
auto it2 = next(it);
if(it2!=S1.end()) k=it2->idx;
ll now=area(j,k)-area(j,i)-area(i,k);
if(now>c) break;
// cout<<"POINTS: "<<j<<' '<<i<<' '<<k<<'\n';
c-=now;
S1.erase({i,e}), S2.erase({i,e});
S1.erase({j,f}), S2.erase({j,f});
edge g; g.x=e.x+f.x, g.y=e.y+f.y;
S1.insert({j,g}), S2.insert({j,g});
// cout<<S1.size()<<", "<<S2.size()<<'\n';
}
{
edge ans=S2.get().e;
int x=ans.x, y=ans.y, g=gcd(x,y);
printf("%d/%d\n", y/g,x/g);
}
return 0;
}
