#pragma GCC optimize("Ofast")
#include<bits/stdc++.h>
bool Mbg;
using namespace std;
#define vec vector
#define pb push_back
#define eb emplace_back
#define siz(vec) ((int)(vec).size())
#define all(vec) (vec).begin(),(vec).end()
template<class T>
void operator +=(vec<T> &a,T b){a.push_back(b);}
template<class T>
void operator --(vec<T> &a){a.pop_back();}
#define pii pair<int,int>
#define x first
#define y second
#define mp make_pair
#define exc(exp) if(exp)continue;
#define stop(exp) if(exp)break;
#define ret(exp) if(exp)return;
#define deb(var) cerr<<#var<<'='<<(var)<<"; "
#define debl(var) cerr<<#var<<'='<<(var)<<";\n"
#define ins insert
#define era erase
#define lb lower_bound
#define int long long
#define inf (long long)(1e9)
template<class T>
bool Min(T &x,T y){return x>y?x=y,1:0;}
template<class T>
bool Max(T &x,T y){return x<y?x=y,1:0;}
const int mod=998244353;
void Add(int &x,int y){x=x+y<mod?x+y:x+y-mod;}
void Dec(int &x,int y){x=x>=y?x-y:x-y+mod;}
int fpm(int x,int y){
    int ans=1;for(;y;y>>=1,(x*=x)%=mod)if(y&1)(ans*=x)%=mod;return ans;
}

int n,m,a[16];

map<int,bool> ans;
map<vec<pii>,bool> f[16];
void dfs(int i,int s,vec<pii> v){
    ret(s>m);
    ret(siz(v)>i+1);

    if(i==0){
        if(siz(v)==1&&v[0].x>m){
            ans[s]=1;
        }
        return;
    }
    int t=0;
    for(auto x:v){
    	t+=x.x;
	}
	for(int j=i;j;j--)t+=a[j];
	ret(t<=m);

	
    sort(all(v));
    if(f[i].find(v)!=f[i].end())return;

    f[i][v]=1;

    auto w=v;
    bool fl=1;
    for(auto &x:w){
        if(x.y>=a[i]){
            fl=0;
            break;
        }
        Min(x.x,a[i]);
    }
    if(fl)dfs(i-1,s,w);

    for(int x=0;x<siz(v);x++){
        exc(x>0&&v[x-1].x==v[x].x);
        for(int y=x+1;y<siz(v);y++){
            exc(y>x+1&&v[y-1].x==v[y].x);
            vec<pii> w;
            for(int k=0;k<siz(v);k++)
                if(k!=x&&k!=y)w+=v[k];
            w+={v[x].x+v[y].x+a[i],v[x].y+v[y].y+a[i]};
            dfs(i-1,s+a[i],w);
        }
    }
}
void work(){
    cin>>m>>n;
    for(int i=1;i<=n;i++){
        cin>>a[i];
    }

    vec<pii> v;
    for(int i=1;i<=n+1;i++){
        v+={m+1,0ll};
        dfs(n,0,v);
    }

    // sort(all(ans));
    // ans.era(unique(all(ans)),ans.end());
    cout<<siz(ans)<<'\n';
    for(auto x:ans)cout<<x.x<<' ';
}
bool Med;
signed main(){
    ios::sync_with_stdio(0),
    cin.tie(0),cout.tie(0);
    int T=1;while(T--)work();
    // cerr<<"Time: "<<clock()<<" ms;\n";
    // cerr<<"Memory: "<<abs(&Med-&Mbg)/1024.0/1024.0<<" MiB.\n";
}
/*
- CONTINUE, NON-STOPPING, FOR THE FAITH
- START TYPING IF YOU DON'T KNOW WHAT TO DO
- STOP TYPING IF YOU DON'T KNOW WHAT YOU'RE DOING
*/