#include<bits/stdc++.h>

using namespace std;

int n, m;
bool zam;
int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(0); cout.tie(0);

    cin >> n >> m;
    if(n<m) {
        swap(n, m);
        zam=1;
    }
    if(m%2==1 && m<n) {
        cout << m+n-1 << "\n";
        for(int i=1; i<=m; i++) {
            if(zam) cout << i << ' ' << 1 << "\n" << i << ' ' << n << "\n";
            else cout << 1 << ' ' << i << "\n" << n << ' ' << i << "\n";
        }
        for(int i=m/2+2; i<=n-m/2-1; i++) {
            if(zam) cout << m/2+1 << ' ' << i << "\n";
            else cout << i << ' ' << m/2+1 << "\n";
        }
    }
    else if(m==n) {
        cout << m+n-2 << "\n";
        for(int i=1; i<=m; i++) {
            cout << 1 << ' ' << i << "\n";
        }
        for(int i=2; i<m; i++) {
            cout << n << ' ' << i << "\n";
        }
    }
    else if(n%2==1) {
        cout << m+n-1 << "\n";
        for(int i=1; i<=m; i++) {
            if(zam) cout << i << ' ' << 1 << "\n" << i << ' ' << n << "\n";
            else cout << 1 << ' ' << i << "\n" << n << ' ' << i << "\n";
        }
        for(int i=m/2+2; i<=n-m/2-1; i+=2) {
            if(zam) cout << m/2+1 << ' ' << i << "\n";
            else cout << i << ' ' << m/2+1 << "\n";
        }
    }
    else {
        cout << m+n-2 << "\n";
        for(int i=1; i<=m; i++) {
            if(zam) cout << i << ' ' << 1 << "\n" << i << ' ' << n << "\n";
            else cout << 1 << ' ' << i << "\n" << n << ' ' << i << "\n";
        }
        for(int i=m/2+2; i<=n-m/2-1; i+=2) {
            if(zam) cout << m/2+1 << ' ' << i << "\n";
            else cout << i << ' ' << m/2+1 << "\n";
        }
    }
}