LA3621(dfs)

#include <iostream>
using namespace std;
#include <cstring>
#include <algorithm>
#include <stdio.h>

const int MAXN = 1010;
const int INF = 0x3f3f3f3f;

int arr[MAXN],num;

int dfs(int n,int step) {
if(num > step)
return 0;
if(arr[num] == n)
return 1;
if(arr[num] << (step - num) < n)
return 0;
for(int i = 0; i <= num; i++) {
num++;
arr[num] = arr[num - 1] + arr[i];
if(arr[num] <= 10000 && dfs(n,step))
return 1;
arr[num] = arr[num - 1] - arr[i];
if(arr[num] > 0 && dfs(n,step))
return 1;
num--;
}
return 0;
}

int main() {
int n;
while(scanf("%d",&n) != EOF && n) {
int i;
for(i = 0;;i++) {
arr[num = 0] = 1;
if(dfs(n,i))
break;
}
printf("%d\n",i);
}
return 0;
}