#include <bits/stdc++.h>
#define int long long
#define PB push_back
#define MP make_pair
#define PII pair<int, int>
#define FOR(i, l, r) for (int i = (l); i <= (r); ++i)
#define ROF(i, r, l) for (int i = (r); i >= (l); --i)
#define FI first
#define SE second
#define SZ size()
using namespace std;
const int N = 2e5 + 5;
const int mod = 998244353;
const int inf = 1e18;
int n, m, cnt;
bool flag;
PII ans[N];
signed main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    cin >> n >> m;
    if (n > m) {
        swap(n, m);
        flag = 1;
    }
    if (n == 2 && m == 2) {
        cout << n + m - 2 << '\n';
        FOR (i, 1, n) {
            if (!flag) {
                cout << i << ' ' << 1 << '\n';
            } else {
                cout << 1 << ' ' << i << '\n';
            }
        }
        return 0;
    }
    if (n == m) {
        cout << n + m - 2 << '\n';
        FOR (i, 1, n) {
            cout << i << ' ' << 1 << '\n';
        }
        FOR (i, 2, n - 1) {
            cout << i << ' ' << m << '\n';
        }
        return 0;
    }
    cout << n + m - 1 << '\n';
    FOR (i, 1, n) {
        ans[++cnt] = MP(i, 1);
        ans[++cnt] = MP(i, m);
    }
    if (n & 1) {
        FOR (i, n / 2 + 1, m - n / 2) {
            ans[++cnt] = MP(n / 2 + 1, i);
        }
    } else {
        FOR (i, n / 2 + 2, m - n / 2 - 1) {
            ans[++cnt] = MP(n / 2, i);
            ans[++cnt] = MP(n / 2 + 1, i);
            ++i;
        }
    }
    FOR (i, 1, cnt) {
        if (flag) {
            cout << ans[i].SE << ' ' << ans[i].FI << '\n';
        } else {
            cout << ans[i].FI << ' ' << ans[i].SE << '\n';
        }
    }
    return 0;
}