#include <iostream>
#include <cstring>
#include <algorithm>
#include <cmath>
#include <cstdio>
using namespace std;

const int N = 1e5 + 10;
const int eps = 1e-8;
const int INF = 1e9 +10;

struct people {
    int p,v,tmp;
} f[N];
long double g[N];

int n,k;

bool cmp(people A,people B)
{
    return A.p < B.p;
}
bool cmp1(people A,people B)
{
    return A.tmp < B.tmp;
}
int check(double mid){
    for (int i = 1; i <= n; i ++ )
        f[i].tmp = f[i].p + f[i].v*mid;
    sort(f + 1, f + n + 1,cmp);  
    int t = 0;
    for (int i = 1; i <= n; i ++ )
    {
        if(!t || g[t] < f[i].tmp) g[++ t] = f[i].tmp;  
        if(t && fabs(g[t]-f[i].tmp) < eps) continue;  
        g[upper_bound(g + 1, g + t + 1,f[i].tmp)-g] = f[i].tmp;  
    }
    return t + k >= n;  
}



int main()
{
    cin >> n >> k;
    for (int i = 1; i <= n; i ++ )
    {
        int p,v;
        cin >> p >> v;
        f[i] = (people){p,v};
    }
    
    sort(f + 1,f + 1 + n, cmp);
    
    
    double l = 0,r = INF + 1,mid;
    for(int i = 1; i <= log2(INF)*log2(INF); i ++ ) {
        mid = (l + r)/2.0;
        if(check(mid)) l = mid;
        else r = mid;
    }

    if(mid > INF/5) return puts("FOREVER"),0;
    return printf("%.4lf",mid),0;
}