#include <iostream>
#include <vector>

using namespace std;
typedef pair<int,int> pi;
int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    int n,m;cin>>n>>m;
    int flag=0;
    vector<pi> ans;
    if(n>m)
    {
        flag=1;
        int t=n;
        n=m;
        m=t;
    }
    if(n==m)
    {
        cout<<n*2-2<<'\n';
        for(int i=1;i<=n;i++)
        {
            cout<<"1 "<<i<<'\n';
        }
        for(int i=2;i<n;i++)
        {
            cout<<n<<' '<<i<<'\n';
        }
        return 0;
    }
    else if(n%2==1)
    {
        for(int i=1;i<=n;i++)
        {
            if(i%2)ans.push_back({i,1});
            if(i%2==m%2)ans.push_back({i,m});
        }
        int lb=n/2+2,rb=n/2+2;
        if(m%2==0)rb--;
        for(int i=1+lb;i<=m-rb;i+=2)
        {
            ans.push_back({n/2+1,i});
        }

        for(int i=1;i<=n;i++)
        {
            if(i%2==0)ans.push_back({i,1});
            if(i%2!=m%2)ans.push_back({i,m});
        }
        lb=n/2+1,rb=n/2+2;
        if(m%2==1)rb--;
        for(int i=1+lb;i<=m-rb;i+=2)
        {
            ans.push_back({n/2+1,i});
        }
    }
    else
    {
        for(int i=1;i<=n;i++)
        {
            if(i%2)
            {
                ans.push_back({i,1});
                ans.push_back({n+1-i,1});
            }
            if(i%2==m%2)
            {
                ans.push_back({i,m});
                ans.push_back({n+1-i,m});
            }
        }
        int lb=n/2+1,rb=n/2+1;
        if(m%2==0)rb++;
        for(int i=1+lb;i<=m-rb;i+=2)
        {
            ans.push_back({n/2,i});
            ans.push_back({n+1-n/2,i});
        }
    }
    cout<<ans.size()<<'\n';
    for(int i=0;i<ans.size();i++)
    {
        if(flag)cout<<ans[i].second<<' '<<ans[i].first<<'\n';
        else cout<<ans[i].first<<' '<<ans[i].second<<'\n';
    }
}