#include <iostream>
#include <cstdio>
#include <string>
#include <algorithm>
#include <cstring>
#include <vector>
#include <cmath>
#include <queue>

using namespace std;
#define rep(i, a, b) for(int i = a; i <= b; ++ i)

long long T, n, m, a[105], b[105];

int main() {
	cin >> T;
	while(T --) {
		cin >> n >> m;
		rep(i, 1, n) cin >> a[i];
		rep(i, 1, m) cin >> b[i];
		rep(j, 1, m) {
			long long mx = -1e11; int flg = 0;
			rep(i, 1, n) if(b[j] - a[i] > mx) mx = b[j] - a[i], flg = i;
			a[flg] = b[j];
		}
		long long ans = 0;
		rep(i, 1, n) ans += a[i];
		cout << ans << endl;
	}
	return 0;
}