#include <bits/stdc++.h>
using namespace std;
typedef long long ll;

vector<pair<int,int>> ans;
void solve(){
    int n,m;cin>>n>>m;
    bool flag=false;
    if(n==m){
        for(int i=1;i<=n;i++)ans.push_back({1,i});
        for(int i=2;i<=n-1;i++)ans.push_back({n,i});
    }
    else{
        if(m<n)swap(m,n),flag=true;
        int t=0;
        for(int j=1;j<=m-n;j+=n){
            t=j;
            for(int i=1;i<=n;i++){
                ans.push_back({i,j});
            }
        }
        for(int i=1;i<=n;i++)ans.push_back({i,m});
        int p=(n+1)/2;
        if(n%2){
            for(int i=t+(n+2)/2;i<=m-(n+2)/2;i++){
                ans.push_back({p,i});
            }
        }
        else{
            for(int i=t+(n+2)/2;i<=m-(n+2)/2;i+=2){
                ans.push_back({p,i});
                ans.push_back({p+1,i});
            }
        }
    }
    cout<<ans.size()<<"\n";
    for(int i=0;i<ans.size();i++){
        if(!flag)cout<<ans[i].first<<" "<<ans[i].second<<" "<<"\n";
        else cout<<ans[i].second<<" "<<ans[i].first<<" "<<"\n";
    }
}

int main(){
    ios::sync_with_stdio(0);
    cin.tie(0);cout.tie(0);
    int n=1;
    //cin>>n;
    while(n--)solve();
    return 0;
}