#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define MAX(a,b) (a > b ? a : b)
#define MIN(a,b) (a < b ? a : b)
const int inf = 1000000000; // 10^9

int main(){
   long long int x,y,h;scanf("%lld %lld %lld",&x,&y,&h);
   int ans=0;
   x *= 1000;
   y *= 1000;
   //printf("X:%lld,y:%lld,h:%lld",x,y,h);
   while(1){
      if(x>h){
         //printf("x:%lld,h:%lld\n",x,h);
         x/=2;
         h*=2;
         ans++;
      }else if(y>h){
         //printf("y:%lld,h:%lld\n",y,h);
         y/=2;
         h*=2;
         ans++;
      }else break;
   }
   printf("%d\n",ans);
}