#include <bits/stdc++.h>

#define ll long long
#define fi first
#define se second

using namespace std;

const int maxn = 1e5 + 10;

int n, m;

int main(){
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	
	cin >> n >> m;
	
	if(m == n){
		cout << 2 * m - 2 << "\n";
		
		for(int i = 1; i <= m; i++){
			cout << 1 << ' ' << i << "\n";
		}
		
		for(int i = 2; i <= m - 1; i++){
			cout << n << ' ' << i << "\n";
		}
		
		return 0;
	}
	
	bool f = 0;
	
	if(n < m){
		f = 1;
		swap(n, m);
	}
	
	if(m % 2 == 1){
		cout << n + m - 1 << "\n";
		
		for(int i = 1; i <= m; i++){
			if(!f) cout << 1 << ' ' << i << "\n";
			else cout << i << ' ' << 1 << "\n";
		}
		
		for(int i = 1; i <= m; i++){
			if(!f) cout << n << ' ' << i << "\n";
			else cout << i << ' ' << n << "\n";
		}
		
		for(int i = m / 2 + 2; i <= n - m / 2 - 1; i++){
			if(!f) cout << i << ' ' << m / 2 + 1 << "\n";
			else cout << m / 2 + 1 << ' ' << i << "\n";
		}
	}
	else {
		cout << n + m - 1 - (n % 2 == 0) << "\n";
		
		for(int i = 1; i <= m; i++){
			if(!f) cout << 1 << ' ' << i << "\n";
			else cout << i << ' ' << 1 << "\n";
		}
		
		for(int i = 1; i <= m; i++){
			if(!f) cout << n << ' ' << i << "\n";
			else cout << i << ' ' << n << "\n";
		}
		
		for(int i = m / 2 + 2; i <= n - m / 2 - 1; i += 2){
			if(!f) cout << i << ' ' << m / 2 << "\n";
			else cout << m / 2 << ' ' << i << "\n";
			
			if(!f) cout << i << ' ' << m / 2 + 1 << "\n";
			else cout << m / 2 + 1 << ' ' << i << "\n";
		}
	}
	
	return 0;
}