#include <bits/stdc++.h>
using namespace std;

#define sc( x ) scanf( "%d" , &x )
#define REP( i , n ) for( int i = 0 ; i < n ; i++ )
#define clr( t , val ) memset( t , val , sizeof(t) )

#define all(v)  v.begin() , v.end()
#define pb push_back
#define SZ( v ) ((int)(v).size())

#define mp make_pair
#define fi first
#define se second

#define test() puts("************test************");
#define DEBUG( x ) cout <<  #x << "=" << x << endl;
#define DEBUG2( x , y ) cout << #x << "=" << x << " " << #y << "=" << y << endl;

#define N 400
#define INF 1000000000

typedef long long ll;
typedef pair< int , int > pii;
typedef vector< int > vi;
typedef vector< vi > vvi;

bool used[ N + 5 ][ N + 5 ];
int memo[ N + 5 ][ N + 5 ];
int A[ 2 ][ N + 5 ];
int n;
int dp( int pos , int cur ){
    if( pos == n ) return cur == 0 ? 0 : INF;
    if( used[ pos ][ cur ] ) return memo[ pos ][ cur ];
    used[ pos ][ cur ] = 1;
    int &dev = memo[ pos ][ cur ] = dp( pos + 1 , cur );
    REP( k , 2 )
        if( cur ) dev = min( dev , A[ k ][ pos ] + dp( pos + 1 , cur - 1 ) );
    return dev;
}


int main(){
    int m;
    while( sc( m ) == 1 ){
        sc( n );
        REP( k , 2 ) REP( i , n ) sc( A[ k ][ i ] );
        clr( used , 0 );
        printf( "%d\n" , dp( 0 , m ) );
    }
}