func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     int t;     cin >> t;     while (t--) {       int n, m;       cin >> n >> m;       int a[n], b[n];       for (int i = 0; i < n; i++) cin >> a[i];       for (int i = 0; i < n; i++) cin >> b[i];       sort(a, a + n);       sort(b, b + n);       int j = 0, k = n - 1;       while (m--) {         if (a[j] < b[k]) swap(a[j], b[k]);         j++;         k--;       }       int sum = 0;       for (int i = 0; i < n; i++) sum = sum + a[i];       cout << sum << endl;     }   }   