uva 1374 快速幂计算

#include <iostream>
#include <cstdio>
#include <cmath>
#include <cstring>
#include <algorithm>
#include <cstdlib>
#include <stack>
#include <cctype>
#include <string>
#include <malloc.h>
#include <queue>
#include <map>
 
using namespace std;
 
const int INF = 0xffffff;
const double esp = 10e-;
const double Pi =  * atan(1.0);
const int Maxn = +;
const long long mod =  ;
const int dr[] = {,,-,,-,,-,};
const int dc[] = {,,,-,,-,-,};
typedef long long LL;
 
LL gac(LL a,LL b){
    return b?gac(b,a%b):a;
}
 
int n,ans[Maxn],maxd;
bool vis[Maxn];
 
int dfs(int step,int s){
    ans[step] = s;
    if(step == maxd){
        if(vis[n])
            return ;
        return ;
    }
    if(ans[step] >  || s *  << (maxd-step) < n){
        return ;
    }
    for(int i = ;i<= step;i++){
        int t = s + ans[i];
        if(!vis[t]){
            vis[t] = ;
            if(dfs(step+,t))
                return ;
            vis[t] = ;
        }
        t = abs(s-ans[i]);
        if(t >  && !vis[t]){
            vis[t] = ;
            if(dfs(step+,t))
                return ;
            vis[t] = ;
        }
    }
    return ;
}
 
int main()
{
#ifndef ONLINE_JUDGE
    freopen("inpt.txt","r",stdin);
#endif
    while(~scanf("%d",&n) && n){
 
        for(maxd = ;;maxd++){
            memset(vis,,sizeof(vis));
            vis[] = ;
            if(dfs(,)){
                printf("%d\n",maxd);
                break;
            }
        }
    }
    return ;
}