[題解]（迭代加深）POJ2248_Addition Chains

#include<iostream>
#include<cstdio>
#include<cstring>
using namespace std;
const int maxn=10009;
int n,x[maxn],ceil;
bool c[109];
bool dfs(int dep,int now){
    if(dep>ceil)return x[ceil]==n;
    for(int i=now-1;i>=1;i--){
        for(int j=i;j>=1;j--){//必須從i開始 
            if(x[i]+x[j]<=x[now-1])break;
            if(c[x[i]+x[j]])continue;
            x[now]=x[i]+x[j];
            if(dfs(dep+1,now+1))return 1;
        }
    }return 0;
}
int main(){
    while(scanf("%d",&n)!=EOF){
        if(n==0)break;
        ceil=1;
        memset(x,0,sizeof(x));
        memset(c,0,sizeof(c));
        x[1]=1;
        while(!dfs(2,2))ceil++;
        for(int i=1;i<=ceil;i++)printf("%d ",x[i]);
        printf("\n");
    }
}