#include <cstdio>
#include <iostream>
#include <algorithm>
#include <string>
#include <cstring>
#include <vector>
#include <queue>
#include <set>
#include <map>
#include <cmath>
#include <iomanip>
#include <cassert>
#include <bitset>
using namespace std;

#define rep(i, n) for (int i=0; i<(n); i++)
#define all(c) (c).begin(), (c).end()
#define uniq(c) c.erase(unique(all(c)), (c).end())
#define index(xs, x) (int)(lower_bound(all(xs), x) - xs.begin())
#define _1 first
#define _2 second
#define pb push_back
#define INF (1LL<<60)
#define MOD 1000000007
#define MAX_N (1<<18)
typedef pair<long long, long long> Node;
Node seg[MAX_N*2-1];
Node op(Node a, Node b) {
  return Node(max(a._1+b._1, a._2+b._2), max(a._1+b._2, a._2+b._1));
}
void update(int k, int v) {
  k += MAX_N-1;
  seg[k] = Node(0, v);
  while (k > 0) {
    k = (k-1)/2;
    seg[k] = op(seg[k*2+1], seg[k*2+2]);
  }
}
Node query(int a, int b, int k=0, int l=0, int r=MAX_N) {
  if (b <= l || r <= a) return Node(0, -INF);
  if (a <= l && b <= r) return seg[k];
  return op(query(a, b, k*2+1, l, (l+r)/2), query(a, b, k*2+2, (l+r)/2, r));
}

int N, Q;
int A[200000], B[200000];

signed main() {
  ios::sync_with_stdio(false); cin.tie(0);
  rep(i, MAX_N*2-1) seg[i] = Node(0, -INF);

  cin >> N >> Q;
  N *= 2;
  rep(i, N) cin >> A[i];
  rep(i, N) cin >> B[i];
  long long base = 0;
  rep(i, N) {
    if (i > 0 && i < N-1) update(i-1, B[i]-A[i]);
    base += A[i];
  }
  rep(i, Q) {
    int p, a, b;
    cin >> p >> a >> b;
    p--;
    base -= A[p];
    A[p] = a, B[p] = b;
    base += A[p];
    if (p > 0 && p < N-1) update(p-1, B[p]-A[p]);
    cout << base+query(0, MAX_N)._1 << "\n";
  }
  return 0;
}
