#pragma comment(linker, "/STACK:1024000000,1024000000")

#include<cstdio>

#include<cstring>

#include<cstdlib>

#include<algorithm>

#include<iostream>

#include<sstream>

#include<cmath>

#include<climits>

#include<string>

#include<map>

#include<queue>

#include<vector>

#include<stack>

#include<set>

using namespace std;

typedef long long ll;

typedef unsigned long long ull;

typedef pair<int,int> pii;

#define pb(a) push(a)

#define INF 0x1f1f1f1f

#define lson idx<<1,l,mid

#define rson idx<<1|1,mid+1,r

#define PI  3.1415926535898

template<class T> T min(const T& a,const T& b,const T& c) {

    return min(min(a,b),min(a,c));

}

template<class T> T max(const T& a,const T& b,const T& c) {

    return max(max(a,b),max(a,c));

}

void debug() {

#ifdef ONLINE_JUDGE

#else

    freopen("in.txt","r",stdin);

    freopen("d:\\out1.txt","w",stdout);

#endif

}

int getch() {

    int ch;

    while((ch=getchar())!=EOF) {

        if(ch!=' '&&ch!='\n')return ch;

    }

    return EOF;

}

const int maxn = 1e5+;

bool canbe[maxn];

int canbeset[maxn];

int first[maxn];

char op[maxn];

int id[maxn];

int main()

{

    int n,m;

    scanf("%d%d", &n, &m);

    for(int i = ; i <= m; i++ )

    {

        op[i] = getch();

        scanf("%d", &id[i]);

        if( first[id[i]] ==  )

            first[id[i]] = op[i] == '+' ?  : -;

    }

    int cnt=;

    int sz=;

    for(int i=;i<=n;i++)

    {

        if(first[i]==-)

            cnt++;

        if(first[i]==)

            canbeset[sz++]=i;

    }

    for(int i=;i<=n;i++) canbe[i] = true;

    if(cnt>) for(int i=;i<=n;i++)

        if(first[i]==) canbe[canbeset[--sz]] = false;

    for(int i=;i<=m;i++)

    {

        if(op[i]=='+')

        {

            if(cnt>) canbe[id[i]]=;

            cnt++;

            while(sz)

            {

                sz--;

                if(canbeset[sz]!=id[i]) canbe[canbeset[sz]]=;

            }

        }else

        {

            cnt--;

            if(cnt>) canbe[id[i]]=;

            if(canbe[id[i]]) canbeset[sz++]=id[i];

        }

    }

    sz=;

    for(int i=;i<=n;i++)

        if(canbe[i])

            canbeset[sz++]=i;

    printf("%d\n",sz);

    for(int i=;i<sz;i++)

        printf("%d%c",canbeset[i],i==sz-?'\n':' ');

    return ;

}