#include<bits/stdc++.h>
using namespace std;
#define time chrono::system_clock::now().time_since_epoch().count()
mt19937_64 rnd(time);
#define maxn 1000005
#define int long long

int read() {int x;cin>>x;return x;}

signed main()
{
	ios::sync_with_stdio(false);
	cin.tie(0);cout.tie(0);

	int n = read(), m = read(), op = 0;
	if(n > m) swap(n, m), op = 1;
	vector<pair<int,int>>ans;
	if(n == 1) {
		for(int i = 1; i <= m; i++) {
			ans.push_back({i, 1});
		}
		cout << ans.size() << "\n";
		for(auto [x, y]:ans) {
			if(!op) cout << y << " " << x <<"\n";
			else cout << x << " " << y <<"\n";
		}
		return 0;
	}
	int x = (n + 1) / 2;
	int y = n / 2;
	vector<int>vis(n + m + n + m);
	vector vis1 = vis;
	for(int i = 1; i <= m; i += 2 * x) {
		for(int j = 1; j <= n; j += 2) {
			assert(vis[i - j + n] == 0);
			ans.push_back({i, j});
			vis[i - j + n] = 1;
			vis1[i + j] = 1; 
		}
	}
	int ba = 1, oo = 0;
	// if(n % 2 == 1) ba = 2;
	// else ba = 1;
	for(int i = ba; i <= m;) {
		int fi;
		if(oo == 0) fi = 2;
		else fi = 1;
		for(int j = fi; j <= n; j += 2) {
			assert(vis[i - j + n] == 0);
			ans.push_back({i, j});
			vis[i - j + n] = 1;
			vis1[i + j] = 1; 
		}
		if(x == y) {
			i += 2 * y;
			continue;
		} 
		if(oo == 0) {
			oo = 1;
			i ++;
			i += 2 * y;
		}
		else {i += 2 * x;}
	}
	for(int i = 1; i <= n; i++) {
		if(vis[m - i + n] == 0 && vis1[m + i] == 0) {
			vis[m - i + n] = 1;
			vis1[m + i] = 1;
			ans.push_back({m, i});
		}
	}
	cout << ans.size() << "\n";
	for(auto [x, y]:ans) {
		if(!op) cout << y << " " << x <<"\n";
		else cout << x << " " << y <<"\n";
	}
}