#include <bits/stdc++.h>
using namespace std;

#define ll long long
#define all(x) x.begin(), x.end()
#define pb push_back
#define mp make_pair
#define ps push
#define in insert
#define f first
#define s second
#define nl cout<<"\n"
#define ca(v) for(auto i:v) cout<<i<<" ";
#define cbit(x) __builtin_popcount(x)
#define gcd(a, b) __gcd(a, b)
#define lcm(a, b) (a*b/gcd(a, b))
const int xm[4] = {-1, 1, 0, 0};
const int ym[4] = {0, 0, -1, 1};
const int MOD = 1e9 + 7;
const int MAXN = 5e5 + 5;
const ll POW = 9973;


#define FOR(i,a,b) for(int i=a;i<b;i++)
#define For(i,a) FOR(i,0,a)
#define vi vector<int>
#define vl vector<ll>
#define trav(a,b) for(auto& a:b)
#define pi pair<int,int>
#define vpi vector<pi>

const int MX = 1e5+5;
bool flipped = false;

vpi v;

void pr(int i, int j) {
    if (flipped) {
        v.pb({j,i});
        // cout << j << " " << i << '\n';
    } else {
        v.pb({i,j});
        // cout << i << " " << j << '\n';
    }
}
void ps() {
    trav(x, v) {
        cout << x.f << " " << x.s << '\n';
    }
}
int main()
{
    ios_base::sync_with_stdio(0); cin.tie(0);
    if (fopen("input.in", "r")) {
        freopen("input.in", "r", stdin);
        freopen("output.out", "w", stdout);
    }
    ll n,m;cin>>n>>m;
    if (m<n) {
        flipped = true;
        swap(n,m);
    }
    
    if (m%n==0) {
        ll ans = m/n* n + (n-2);
        cout << ans << '\n';
        for(int bi=0;bi<m/n;bi++) {
            FOR(j,1,n+1) {
                pr(bi*n+1, j);
            }
        }
        FOR(j,2,n) {
            pr(m, j);
        }
        ps();
    } else {
        // ll ans = (m/n-1)*n + (m%n)-1+2*n;
        // cout << ans << '\n';
        for(int bi=0;bi<m/n;bi++) {
            FOR(j,1,n+1) {
                pr(j, bi*n+1);
            }
        }
        if (n%2==0) {
            int ci = (m/n-1)*n;
            int rem = ((m%n)-1)/2 * 2;
            int opp = n-rem;
            
            int mid = ci + (n+(m%n))/2;
            FOR(i, opp/2+1, opp/2+1+rem) {
                pr(i, (ci+m)/2);
            }
        } else {
            int ci = (m/n-1)*n;
            int rem = m%n-1;
            ci += m%n;
            FOR(i,ci, ci+rem) {
                pr(n/2+1, i+1);
            }
        }
        FOR(i,1,n+1) {
            pr(i, m);
        }
        cout << v.size() << '\n';
        ps();
    }
}