#include <iostream>
int*cells;
int max;
void game(int run_count,int id){
    int count = (id & 0x5555) + ((id >> 1) & 0x5555);
    count = (count & 0x3333) + ((count >> 2) & 0x3333);
    count = (count & 0x0f0f) + ((count >> 4) & 0x0f0f);
    count = (count & 0x00ff) + ((count >> 8) & 0x00ff);
	cells[id]=run_count;
	if(id+count<=max&&cells[id+count]>run_count){
		cells[id+count]=run_count;
		game(run_count+1,id+count);
	}
	if(id-count>0&&cells[id-count]>run_count){
		cells[id-count]=run_count;
		game(run_count+1,id-count);
	}
}
int main(){
	std::cin>>max;
	cells=new int[max+1];
	for(int i=1;i<=max;i++){
		cells[i]=max+100;
	}
	game(1,1);
	if(cells[max]==max+100){
		std::cout<<-1<<std::endl;
	}else{
		std::cout<<cells[max]<<std::endl;
	}
	delete[] cells;
}