// #pragma GCC optimize("Ofast,no-stack-protector,unroll-loops",                  \
//                      "omit-frame-pointer", "inline")
// #pragma GCC target(                                                            \
//     "sse,sse2,sse3,ssse3,sse4,sse4.1,sse4.2,popcnt,abm,mmx,avx,avx2,fma,tune=native")
// #pragma GCC option("arch=native", "no-zero-upper") // Enable AVX

/// UH Top
#include <bits/stdc++.h>
#define db(x)   cerr << #x << ':' << (x) << '\n';
#define all(v)  (v).begin(), (v).end()
#define allr(v) (v).rbegin(), (v).rend()
// #define int ll
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
// typedef __int128_t int128;
typedef pair<ll, ll> pii;
typedef pair<ld, ll> pdi;
typedef pair<ld, ld> pdd;
typedef pair<ld, pdd> pdp;
typedef pair<string, ll> psi;
typedef pair<ll, string> pls;
typedef pair<string, string> pss;
typedef pair<ll, pii> pip;
typedef pair<pii, pii> ppp;
typedef complex<ld> point;
typedef vector<point> polygon;
typedef vector<ll> vi;
typedef pair<point, int> ppi;
#define prec(n)                                                                \
	cout.precision(n);                                                         \
	cout << fixed
const ll mod = (1e9 + 7);
const ld eps = (1e-9);
const ll oo = (ll)(1e9 + 5);
#define pi   acos(-1)
#define MAXN (ll)(1e6 + 5)

int32_t main() {
	ios_base::sync_with_stdio(0);
	cin.tie(0);

	int n, m;
	cin >> n >> m;
	vector<pii> ans;
	bool invert = 0;
	if (n > m) {
		swap(n, m);
		invert = 1;
	}

	int last = 1;
	for (int j = 1; j <= m; j += n) {
		for (int i = 0; i < n; i++)
			ans.push_back(pii(i + 1, j));
		last = j;
	}

	int d = m - last;
	// cout << d << "\n";
	if (d > n / 2 && d) {
		int x = d - (n / 2);
		int cnt = 2 * x - (n & 1);
		int l = 1 + (n - d);
		// cout << cnt << "\n";
		for (int i = 0; i < cnt; i++) {
			ans.push_back(pii(l + i, m));
		}
	}

	cout << ans.size() << "\n";
	for (auto p : ans) {
		if (invert)
			swap(p.first, p.second);
		cout << p.first << ' ' << p.second << "\n";
	}

	return 0;
}