#include <stdio.h>

int main() {
	int a,b,c,i,j=0;
for(b=2,c=1;100<=a,a<=1000;){
   a=3*b+2*c;
   c=b;
   b=a;
if(100<=a&&a<=1000){
	j=j+1;
}
}
  printf("%d",j);
return 0;
}