#include <bits/stdc++.h>
#define AquA cin.tie(0);ios_base::sync_with_stdio(0);
#define fs first
#define sc second
#define cd complex<double>
#define p_q priority_queue
#define int long long
using namespace std;
signed main(){
AquA;
int h,w;
cin >> h >> w;
vector<int> v(h),a(w);
for(int i=0;i<h;i++){
cin >> v[i];
}
for(int j=0;j<w;j++){
cin >> a[j];
}
vector<vector<int> > dp(h,vector<int>(w,1e18));
dp[0][0]=0;
for(int i=0;i<h;i++){
for(int j=0;j<w;j++){
if(i){
dp[i][j]=min(dp[i][j],dp[i-1][j]+a[j]);
}
if(j){
dp[i][j]=min(dp[i][j],dp[i][j-1]+v[i]);
}
}
}
cout << dp[h-1][w-1] << "\n";
return 0;
}
