#include<bits/stdc++.h>
using namespace std;
// #define int long long
#define rep(i,j,k) for(int i=(j);i<=(k);i++)
#define per(i,j,k) for(int i=(j);i>=(k);i--)
#define pb push_back
#define mp make_pair
#define fi first
#define se second
typedef vector<int> vi;
typedef pair<int,int> pi;

const int N=2e5+5,inf=1e9+5;
int n,m,a[N],b[N];
int pmn[N],pmx[N],smn[N],smx[N];
int mx0[N],mx1[N];
int le[N],ri[N];
signed main(){
	ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
	
	cin>>n>>m;
	rep(i,1,n){
		cin>>a[i];
	}
	rep(i,1,m){
		cin>>b[i];
	}
	rep(i,1,m){
		pmn[i]=pmx[i]=b[i];
		if(i>=2){
			pmn[i]=min(pmn[i],pmn[i-1]);
			pmx[i]=max(pmx[i],pmx[i-1]);
		}
	}
	per(i,m,1){
		smn[i]=smx[i]=b[i];
		if(i<=m-1){
			smn[i]=min(smn[i],smn[i+1]);
			smx[i]=max(smx[i],smx[i+1]);
		}
	}
	rep(i,1,n){
		int p=upper_bound(pmn+1,pmn+m+1,-a[i],greater<int>())-pmn;
		mx0[i]=(p==1? -inf: pmx[p-1]);
		int q=lower_bound(smn+1,smn+m+1,-a[i])-smn;
		mx1[i]=(q>m? -inf: smx[q]);
	}
	vi stk;
	rep(i,1,n){
		while(!stk.empty() && a[stk.back()]<=a[i]){
			stk.pop_back();
		}
		le[i]=(stk.empty()?0:stk.back());
		stk.pb(i);
	}
	stk.clear();
	per(i,n,1){
		while(!stk.empty() && a[stk.back()]<a[i]){
			stk.pop_back();
		}
		ri[i]=(stk.empty()?n+1:stk.back());
		stk.pb(i);
	}
	int mn=pmn[n];
	long long ans=0;
	rep(i,1,n){
		if(a[i]+mn<0){
			continue;
		}
		int mnl=a[i],mnr=a[i];
		int cntl=0,cntr=0;
		per(j,i,le[i]+1){
			mnl=min(mnl,a[j]);
			int mx=mx0[j];
			if(mx+mnl>=0){
				cntl++;
				mnl=a[j];
			}
		}
		rep(j,i,ri[i]-1){
			mnr=min(mnr,a[j]);
			int mx=mx1[j];
			if(mx+mnr>=0){
				cntr++;
				mnr=a[j];
			}
		}
		// cout<<"?"<<i<<' '<<le[i]<<' '<<ri[i]<<'\n';
		ans+=(long long)cntl*cntr;
	}
	cout<<ans<<'\n';
}