#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define rp(i,a,b)        for(int i=a;i<b;i++)

void solvetask(){
    int n, m;
    cin >> n >> m;
    bool flag = false;
    if(n > m){
        swap(n, m);
        flag = true;
    }
    vector<pair<int, int>> resp;
    int t = 1;
    while(t <= m){
        rp(i, 0, n) resp.push_back({t, i+1});
        t+=n;
    }

    int comp = t - m;
    t = n -= comp*2;

    if(t > 0){
        int d = (n-t)/2;
        rp(i, d, n-d) resp.push_back({m, i+1});
    }
    ll r = resp.size();
    cout << r << "\n";
    for(auto i: resp) if(flag) cout << i.first << " " << i.second << "\n";
    else cout << i.second << " " << i.first << "\n";
}

int main(){
    cin.tie(0)->sync_with_stdio(0);
    ll t = 1;
    while(t--) solvetask();
}