#include <iostream>
#include <chrono>
#define maxn 1005
#define maxlog 20
#define INF 1000000010
#define LINF 1000000000000000005
#define endl '\n'
#define pb(x) push_back(x)
#define X first
#define Y second
#define control cout<<"passed"<<endl;
#pragma GCC optimize("O3" , "Ofast" , "unroll-loops" , "fast-math")
#pragma GCC target("avx2")
using namespace std;
std::chrono::high_resolution_clock::time_point startT, currT;
constexpr double TIME_MULT = 1;
double timePassed()
{
using namespace std::chrono;
currT = high_resolution_clock::now();
double time = duration_cast<duration<double>>(currT - startT).count();
return time * TIME_MULT;
}
int n, m;
int a[maxn], b[maxn];
long long dp[maxn][maxn];
void read()
{
cin >> n >> m;
for(int i = 1; i <= n; i++)
cin >> a[i];
for(int i = 1; i <= m; i++)
cin >> b[i];
}
void calc_dp()
{
for(int i = 1; i <= n; i++)
for(int j = 1; j <= m; j++)
{
if(i == 1 && j == 1)
{
dp[i][j] = 0;
continue;
}
if(i == 1)
{
dp[i][j] = dp[i][j - 1] + a[i];
continue;
}
if(j == 1)
{
dp[i][j] = dp[i - 1][j] + b[j];
continue;
}
dp[i][j] = min(dp[i][j - 1] + a[i] , dp[i - 1][j] + b[j]);
}
cout << dp[n][m] << endl;
}
int main()
{
/**#ifdef ONLINE_JUDGE
freopen("taxi.in", "r", stdin);
freopen("taxi.out", "w", stdout);
#endif*/
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
startT = std::chrono::high_resolution_clock::now();
read();
calc_dp();
return 0;
}
