#include <bits/stdc++.h>
using namespace std;
template <class S, class T>
pair<S, T> operator+(const pair<S, T> &s, const pair<S, T> &t) {
  return pair<S, T>(s.first + t.first, s.second + t.second);
}
template <class S, class T>
pair<S, T> operator-(const pair<S, T> &s, const pair<S, T> &t) {
  return pair<S, T>(s.first - t.first, s.second - t.second);
}
template <class S, class T>
ostream &operator<<(ostream &os, pair<S, T> p) {
  os << "(" << p.first << ", " << p.second << ")";
  return os;
}
template <class T>
bool chmax(T &a, const T &b) {
  if (a < b) {
    a = b;
    return 1;
  }
  return 0;
}
template <class T>
bool chmin(T &a, const T &b) {
  if (a > b) {
    a = b;
    return 1;
  }
  return 0;
}
const long long inf = 1000000001;
const long long INF = 1e18;
const long long MOD = 1000000007;
const double pi = 3.14159265358979323846;
int dx[4] = {1, 0, -1, 0}, dy[4] = {0, 1, 0, -1};
int dx2[8] = {1, 1, 0, -1, -1, -1, 0, 1}, dy2[8] = {0, 1, 1, 1, 0, -1, -1, -1};
int main() {
  int n, q;
  cin >> n >> q;
  n *= 2;
  assert(q <= 10);
  vector<long long> a(n), b(n);
  for (int i = 0; i < (n); i++) {
    cin >> a[i];
  }
  for (int i = 0; i < (n); i++) {
    cin >> b[i];
  }
  cout << endl;
  while (q--) {
    int p, x, y;
    cin >> p >> x >> y;
    p--;
    a[p] = x;
    b[p] = y;
    vector<vector<vector<long long> > > dp(
        n + 1, vector<vector<long long> >(3, vector<long long>(2, -INF)));
    dp[0][0][0] = 0;
    for (int i = 0; i < (n - 1); i++) {
      for (int j = 0; j < (3); j++) {
        for (int k = 0; k < (2); k++) {
          if (dp[i][j][k] <= -INF / 2) continue;
          if (j == 0) {
            chmax(dp[i + 1][1][k], dp[i][j][k] + a[i]);
          } else if (j == 1) {
            chmax(dp[i + 1][2][k], dp[i][j][k] + a[i]);
            chmax(dp[i + 1][1][1 - k], dp[i][j][k] + b[i]);
          } else {
            chmax(dp[i + 1][2][k], dp[i][j][k] + a[i]);
            chmax(dp[i + 1][2][1 - k], dp[i][j][k] + b[i]);
          }
        }
      }
    }
    long long ans = max(dp[n - 1][1][0], dp[n - 1][2][0]) + a[n - 1];
    cout << ans << endl;
  }
}
