#include<bits/stdc++.h>
using namespace std;
inline int read()
{
	int n=0,f=1,ch=getchar();
	while(ch<'0'||ch>'9')
	{
		if(ch=='-')f=-1;
		ch=getchar();
	}
	while(ch>='0'&&ch<='9')
	{
		n=n*10+ch-'0';
		ch=getchar();
	}
	return n*f;
}
set<int>se;
struct qj
{
	int wz,l,r;
}q[200005];
int cnt;
bool bi(struct qj x,struct qj y)
{
	return x.r<y.r;
} 
int qx[200005],qy[200005],tmp;
int main()
{
	int n,m;
	n=read();
	m=read();
	cnt=0;
	for(int i=2;i<=n+m;i+=2)
	{
		int minx=max(1,i-m),maxx=min(n,i-1);
		q[++cnt].wz=i;
		q[cnt].l=minx-i/2;
		q[cnt].r=maxx-i/2;
	}
	sort(q+1,q+cnt+1,bi);
	for(int i=-(n+m);i<=(n+m);i++)se.insert(i);
	for(int i=1;i<=cnt;i++)
	{
		set<int>::iterator it=se.lower_bound(q[i].l);
		if(it==se.end()||(*it)>q[i].r)continue;
		int sth=(*it),nx=sth+q[i].wz/2,ny=q[i].wz-nx;
		se.erase(it);
		qx[++tmp]=nx;
		qy[tmp]=ny;
	}
	cnt=0;
	for(int i=3;i<=n+m;i+=2)
	{
		int minx=max(1,i-m),maxx=min(n,i-1);
		q[++cnt].wz=i;
		q[cnt].l=minx-i/2;
		q[cnt].r=maxx-i/2;
	}
	sort(q+1,q+cnt+1,bi);
	se.clear();
	for(int i=-(n+m);i<=(n+m);i++)se.insert(i);
	for(int i=1;i<=cnt;i++)
	{
		set<int>::iterator it=se.lower_bound(q[i].l);
		if(it==se.end()||(*it)>q[i].r)continue;
		int sth=(*it),nx=sth+q[i].wz/2,ny=q[i].wz-nx;
		se.erase(it);
		qx[++tmp]=nx;
		qy[tmp]=ny;
	}
	printf("%d\n",tmp);
	for(int i=1;i<=tmp;i++)printf("%d %d\n",qx[i],qy[i]);
	return 0;
}