#include <bits/stdc++.h>
#define For(x, y, z) for(int x = (y); x <= z; x++)
#define Rep(x, y, z) for(int x = (y); x >= z; x--)
using namespace std;
const int MAXN = 1e5 + 5;
int n, m, flg;
map<int, int> visy, visx;
vector<pair<int, int> > ans; 
inline void SolveEven() {
    for(int x = 2; x <= n + m; x += 2) {
        if(visx[x]) break; 
        int lj = max(x - n, 1), rj = min(x - 1, m);
        int ly = x - 2 * rj, ry = x - 2 * lj;
        if(!visy[ly]) {
            visy[ly] = 1, visx[x] = 1;
            ans.emplace_back(x - rj, rj);
        } else break;
    }    
    for(int x = n + m - (n + m & 1); x >= 2; x -= 2) {
        if(visx[x]) break; 
        int lj = max(x - n, 1), rj = min(x - 1, m);
        int ly = x - 2 * rj, ry = x - 2 * lj;
        if(!visy[ry]) {
            visy[ry] = 1, visx[x] = 1;
            ans.emplace_back(x - lj, lj);
        } else if(ry != 0) break;
    }
    int pp = 2;
    for(int x = 2; x <= n + m; x += 2) {
        if(visx[x]) continue;
        if(visy[pp]) break;
        int lj = max(x - n, 1), rj = min(x - 1, m);
        int ly = x - 2 * rj, ry = x - 2 * lj;
        if(ly <= pp && pp <= ry) {
            visy[pp] = 1, visx[x] = 1;
            ans.emplace_back(x + pp >> 1, x - pp >> 1);
            pp += 2;
        }
    }    
}
inline void SolveOdd() {
    for(int x = 3; x <= n + m; x += 2) {
        if(visx[x]) break; 
        int lj = max(x - n, 1), rj = min(x - 1, m);
        int ly = x - 2 * rj, ry = x - 2 * lj;
        if(!visy[ly]) {
            visy[ly] = 1, visx[x] = 1;
            ans.emplace_back(x - rj, rj);
        } else break;
    }    
    for(int x = n + m - 1 + (n + m & 1); x >= 3; x -= 2) {
        if(visx[x]) break; 
        int lj = max(x - n, 1), rj = min(x - 1, m);
        int ly = x - 2 * rj, ry = x - 2 * lj;
        if(!visy[ry]) {
            visy[ry] = 1, visx[x] = 1;
            ans.emplace_back(x - lj, lj);
        } else break;
    }
    int pp = 1;
    for(int x = 3; x <= n + m; x += 2) {
        if(visx[x]) continue;
        if(visy[pp]) break;
        int lj = max(x - n, 1), rj = min(x - 1, m);
        int ly = x - 2 * rj, ry = x - 2 * lj;
        if(ly <= pp && pp <= ry) {
            visy[pp] = 1, visx[x] = 1;
            ans.emplace_back(x + pp >> 1, x - pp >> 1);
            pp += 2;
        }
    }    
}
int main() {
    scanf("%d%d", &n, &m);
    if(n < m) swap(n, m), flg = 1;
    SolveEven();
    SolveOdd();
    cout << ans.size() << '\n';
    for(auto [x, y] : ans) {
        if(flg) swap(x, y);
        cout << x << ' ' << y << '\n';
    }
    return 0;
}