#include "fish.h"
#include <bits/stdc++.h>
using namespace std;
long long max_weights(int N, int M, vector<int> X, vector<int> Y, vector<int> W)
{
bool ok = 1;
for (auto &i : X)
ok &= (i % 2 == 0);
if (ok)
return accumulate(W.begin(), W.end(), 0ll);
if (*max_element(X.begin(), X.end()) <= 1)
{
vector<long long> A(N), B(N);
for (int i = 0; i < M; i++)
{
if (X[i])
B[Y[i]] = W[i];
else
A[Y[i]] = W[i];
}
if (N == 2)
{
return max(A[0] + A[1], B[0] + B[1]);
}
long long mx, s;
s = mx = 0;
for (int i = 0; i < N; i++)
{
s += A[i] - B[i];
mx = max(mx, s);
}
return mx + accumulate(B.begin(), B.end(), 0ll);
}
vector<long long> dp(N), A(N + 1);
for (int i = 0; i < M; i++)
A[X[i]] = W[i];
for (int i = 0; i < N; i++)
{
dp[i] = A[i + 1] + (i ? A[i - 1] : 0ll);
if (i > 1)
dp[i] += dp[i - 2] - A[i - 1];
if (i)
dp[i] = max(dp[i], dp[i - 1] - A[i] + A[i + 1]);
if (i > 1)
dp[i] = max(dp[i], dp[i - 2] + A[i + 1]);
if (i > 2)
dp[i] = max(dp[i], dp[i - 3] + A[i + 1] + A[i - 1]);
}
return *max_element(dp.begin(), dp.end());
}
