#include <bits/stdc++.h>
using namespace std;
template <typename T>
T id(T b) {
  return b;
};
template <class It>
bool all(It f, It l) {
  return std::all_of(f, l, id<bool>);
}
template <class It>
bool any(It f, It l) {
  return std::any_of(f, l, id<bool>);
}
const int MAX_N = 100000;
int n, q;
int64_t a[2 * MAX_N], b[2 * MAX_N];
int64_t dp[2 * MAX_N][2];
int main() {
  cin >> n >> q;
  for (int i = 0; i < 2 * n; ++i) {
    cin >> a[i];
  }
  for (int i = 0; i < 2 * n; ++i) {
    cin >> b[i];
  }
  int64_t p, x, y;
  while (q--) {
    cin >> p >> x >> y;
    p--;
    a[p] = x;
    b[p] = y;
    dp[0][0] = a[0];
    dp[0][1] = INT_MIN;
    for (int i = 1; i < 2 * n - 1; i++) {
      dp[i][0] = max(dp[i - 1][0] + b[i], dp[i - 1][1] + a[i]);
      dp[i][1] = max(dp[i - 1][0] + a[i], dp[i - 1][1] + b[i]);
    }
    cout << dp[2 * n - 2][0] + a[2 * n - 1] << endl;
  }
  return 0;
}
