#include <bits/stdc++.h>
using namespace std;
template <class T>
inline bool chmax(T& lhs, const T& rhs) {
  if (lhs < rhs) {
    lhs = rhs;
    return 1;
  }
  return 0;
}
template <class T>
inline bool chmin(T& lhs, const T& rhs) {
  if (lhs > rhs) {
    lhs = rhs;
    return 1;
  }
  return 0;
}
constexpr int MX = 200000;
constexpr long long inf = 1ll << 60;
int N, Q;
int A[MX], B[MX];
long long dp[MX][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];
  while (Q--) {
    int p, a, b;
    cin >> p >> a >> b;
    A[p - 1] = a, B[p - 1] = b;
    for (int i = 0; i < (2 * N); ++i)
      for (int j = 0; j < (2); ++j) dp[i][j] = -inf;
    dp[1][0] = A[0] + A[2 * N - 1];
    for (int i = (1); i <= (2 * N - 2); ++i) {
      chmax(dp[i + 1][0], dp[i][1] + B[i]);
      chmax(dp[i + 1][0], dp[i][0] + A[i]);
      chmax(dp[i + 1][1], dp[i][0] + B[i]);
      chmax(dp[i + 1][1], dp[i][1] + A[i]);
    }
    cout << dp[2 * N - 1][0] << '\n';
  }
}
