func_code_string: #include <bits/stdc++.h>   #pragma GCC optimize( Ofast )   using namespace std;   void manupulate(string &str) {     for (long long int i = 0; i < str.size(); ++i) str[i] -= 48;   }   bool isprime(long long int n) {     if (n <= 1) return false;     for (long long int i = 2; i * i <= n; ++i)       if (n % i == 0) return false;     return true;   }   long long int expo(long long int a, long long int n) {     if (n == 0) return 1;     if (n == 1) return a;     long long int tmp = expo(a, n / 2);     tmp = (tmp * tmp) % (long)(1e9 + 7);     if (n & 1) tmp = (tmp * a) % (long)(1e9 + 7);     return tmp;   }   signed main() {     ios_base::sync_with_stdio(false);     cin.tie(NULL);     cout.tie(NULL);     ;     long long int t;     cin >> t;     while (t--) {       long long int n;       cin >> n;       ;       long long int k;       cin >> k;       ;       long long int ar[n], br[n];       for (long long int i = 0; i < n; ++i) cin >> ar[i];       ;       for (long long int i = 0; i < n; ++i) cin >> br[i];       ;       sort(ar, ar + n);       sort(br, br + n, greater<long long int>());       long long int ans = 0;       long long int x = 0;       for (long long int i = 0; i < k; ++i) {         if (br[i] > ar[i]) {           ans += br[i];           ++x;         }       }       for (long long int i = x; i < n; ++i) ans += ar[i];       cout << ans <<   n ;     }     return 0;   }   