Problem 12

#include<bits/stdc++.h>
using namespace std;
#define pb push_back
#define rep(i,n) for(int i=0;i<int(n);i++)
#define rep1(i,n) for(int i=1;i<=int(n);i++)
#define mp make_pair
#define F first
#define S second
#define IOS ios_base::sync_with_stdio(0); cin.tie(0)
#define INF 0x3f3f3f3f

typedef long long ll;
typedef pair<ll,ll> pii;
typedef pair<double,double> pdd;
const ll mod=1e9+7;
ll n,k;
ll h,w;
ll r[1005],c[1005];
ll d[1005][1005];
ll mypow(ll a,ll b){
    ll res=1LL;
    while(b){
        if(b&1) res=res*a%mod;
        a=a*a%mod;

        b>>=1;
    }
    return res;
}
int main()
{
    IOS;
    while(cin>>h>>w)
    {
        memset(r,0,sizeof(r));
        memset(c,0,sizeof(c));
        memset(d,0,sizeof(d));
        ll sum=0;
        rep1(i,h) cin>>r[i];
        rep1(i,w) cin>>c[i];
        rep1(i,h) rep1(j,r[i]) d[i][j]=1;
        rep1(j,w) rep1(i,c[j]) d[i][j]=1;
        bool flag=true;
        rep1(i,h) if(d[i][r[i]+1]==1) flag=false;
        rep1(j,w) if(d[c[j]+1][j]==1) flag=false;

        //rep1(i,h) {rep1(j,w) cout<<d[i][j]<<" ";cout<<'\n';}
        for(int i=2;i<=h;i++)
        {
            for(int j=2;j<=w;j++)
            {
                //cout<<i<<' '<<j<<' '<<c[]
                if(d[i][j]==0&&i>=c[j]+2&&j>=r[i]+2) sum++;

            }
        }
        if(!flag) cout<<"0\n";
        else cout<<mypow(2,sum)<<'\n';

    }
    return 0;
}