// g++-13 1.cpp -std=c++17 -O2 -I .
#include <bits/stdc++.h>
using namespace std;

using ll = long long;
using ld = long double;
 
using vi = vector<int>;
using vvi = vector<vi>;
using vll = vector<ll>;
using vvll = vector<vll>;
using vld = vector<ld>;
using vvld = vector<vld>;
using vst = vector<string>;
using vvst = vector<vst>;
 
#define fi first
#define se second
#define pb push_back
#define eb emplace_back
#define pq_big(T) priority_queue<T,vector<T>,less<T>>
#define pq_small(T) priority_queue<T,vector<T>,greater<T>>
#define all(a) a.begin(),a.end()
#define rep(i,start,end) for(ll i=start;i<(ll)(end);i++)
#define per(i,start,end) for(ll i=start;i>=(ll)(end);i--)
#define uniq(a) sort(all(a));a.erase(unique(all(a)),a.end())

int main(){
  ios::sync_with_stdio(false);
  cin.tie(nullptr);

  int n,m;cin>>n>>m;

  if(n==1&&m==1){
    cout<<1<<endl;
    cout<<1<<" "<<1<<endl;
    return 0;
  }

  int swaped=0;
  if(n>m){
    swap(n,m);
    swaped=1;
  }

  if(n==m){
    cout<<n+m-2<<endl;
    rep(i,0,n){
      cout<<1<<" "<<i+1<<"\n";
    }
    rep(i,1,n-1){
      cout<<n<<" "<<i+1<<"\n";
    }
    return 0;
  }

  if(n==2){
    vector<pair<int,int>> ans;
    rep(i,0,n){
      rep(j,0,m){
        if(j%2==0){
          int p=i+1,q=j+1;
          if(swaped)swap(p,q);
          ans.emplace_back(p,q);
        }
      }
    }
    cout<<ans.size()<<endl;
    for(auto [p,q]:ans)cout<<p<<" "<<q<<"\n";
    return 0;
  }

  // n <= m
  vector<pair<int,int>> ans;
  rep(i,0,m){
    if(i==0){
      rep(j,0,n){
        ans.emplace_back(j,i);
      }
    }
    else if(n-1<=i&&i+n<=m){
      if(n%2==0){
        if(n!=2&&i%2==1){
          ans.emplace_back(n/2-1,i);
          ans.emplace_back(n/2,i);
        }
        if(n==2&&i%2==0){
          ans.emplace_back(n/2-1,i);
          ans.emplace_back(n/2,i);
        }
      }
      else{
        ans.emplace_back(n/2,i);
      }
    }
    else if(i==m-1){
      if(n==m){
        rep(j,1,n-1){
          ans.emplace_back(j,i);
        }
      }
      else{
        rep(j,0,n){
          ans.emplace_back(j,i);
        }
      }
    }
  }

  cout<<ans.size()<<endl;
  for(auto [x,y]:ans){
    if(swaped){
      swap(x,y);
    }
    cout<<x+1<<" "<<y+1<<"\n";
  }
}

/*
#.#
#.#

####
#...
*/