#include<bits/stdc++.h>
#define REP(i,n) for(int i=0,i##_len=(n);i<i##_len;++i)
#define rep(i,a,b) for(int i=int(a);i<int(b);++i)
#define All(x) (x).begin(),(x).end()
using namespace std;
typedef long long ll;
int ans1(ll x,ll y,ll h){
    x*=1000;y*=1000;
    if(x>y) swap(x,y);
    int res=0;
    while(x>h){
        x=(x+1)/2;
        h*=2;
        res++;
    }
    while(y>h){
        y=(y+1)/2;
        h*=2;
        res++;
    }
    return res;
}
template<typename T> T npow(T x, ll n){
    T ans = 1;
    while(n != 0){
        if(n&1) ans = ans*x;
        x = x*x;
        n = n >> 1;
    }
    return ans;
}
int ans2(ll x,ll y,ll h){
    x*=1000;y*=1000;
    int l=0,r=40;
    while(l+1<r){
        int m=(l+r)/2;
        ll tmp=h*npow(2LL,m);
        bool able=false;
        REP(k,m+1){
            ll th=tmp;
            vector<ll> tx(k+1,x),ty(m-k+1,y);
            REP(i,k) tx[i+1]=(tx[i]+1)/2;
            REP(i,m-k) ty[i+1]=(ty[i]+1)/2;
            int nx=k,ny=m-k;
            while(tx[nx]<=th||ty[ny]<=th){
                if(nx>0&&2*tx[nx-1]>th){
                    nx--; th/=2;
                }
                else if(ny>0 && 2*ty[ny-1]>th){
                    ny--; th/=2;
                }else{ break;}
            }
            if(tx[nx]>th&&ty[ny]>th){
                able = true;
            }
        }
        if(able) l=m;
        else r=m;
    }
    return l;
}
int main(){
    ll x,y,h;cin>>x>>y>>h;
    cout<<ans1(x,y,h)<<endl;
}