#include <bits/stdc++.h>
using namespace std;
#define ll long long
const int MAX = 1e5 + 10, inf = 2e9, mod = 998244353;

vector<pair<int, int>> ans;
void dfs(int x, int y, int n, int m){
	if (n == 0 or m == 0) return;
	if (n < m){
		for (int i = x; i <= x + n - 1; ++ i) ans.push_back({i, y});
		dfs(x, y + n, n, m - n);
	}
	else if (n > m){
		for (int i = y; i <= y + m - 1; ++ i) ans.push_back({x, i});
		dfs(x + m, y, n - m, m);
	}
	else{
		for (int i = x; i <= x + m - 1; ++ i) ans.push_back({i, y});
		if (n > 2)
		for (int i = x + 1; i <= x + m - 2; ++ i) ans.push_back({i, y + n - 1});
	}
}
void solve(){
	int n, m;
	cin >> n >> m;
	dfs(1, 1, n, m);
	cout << ans.size() << endl;
	for (auto p: ans) cout << p.first << ' ' << p.second << endl;
}
signed main(){
    ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
    //cout << fixed << setprecision(10);
    //while (cin >> n)
    //int _;cin >> _;while (_ --)
    	solve();
    return 0;
}