Programming contest

input/code.cpp: In function 'void solve()':
input/code.cpp:46:9: error: increment of read-only variable 'i'
   46 |     FOR(i,0,K) f[i]=-inf;
      |         ^
input/code.cpp:8:64: note: in definition of macro 'FOR'
    8 | #define FOR(i, a, b) for(__typeof(b) i = a, _b = b; i <= _b; ++i)
      |                                                                ^

// #ifdef ONLINE_JUDGE
// #pragma GCC optimize("O3,unroll-loops")
// #pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")
// #endif
#include "bits/stdc++.h"
#define fast ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
#define fill(arr,val) memset(arr,val,sizeof(arr))
#define FOR(i, a, b) for(__typeof(b) i = a, _b = b; i <= _b; ++i)
#define FORD(i, a, b) for(__typeof(a) i = a, _b = b; i >= _b; --i)
#define ALL(a) (a).begin(), (a).end()
#define YES cout << "YES\n"
#define NO cout << "NO\n"
#define ll long long
#define fi first
#define se second
#define pb push_back
#define pf push_front
#define ii pair<int,int>
#define iii pair<int,pair<int,int>>
#define dq deque<int>
#define nend '\n'
using namespace std;

const ll inf = 1e18;
const int dx[] = {1,0,-1,0};
const int dy[] = {0,1,0,-1};
const int MOD = 1e9 + 7;
const ll hashi = 2e9 + 11;

void init_code() {
    fast;
    #ifndef ONLINE_JUDGE
    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);
    #endif
}

const int K = 1500;
ll f[K+1];
void solve() {
    int n;
    cin >> n;
    vector<ll> m(n), p(n);
    for (auto& x : m) cin >> x;
    for (auto& x : p) cin >> x;
    FOR(i,0,K) f[i]=-inf;
    f[0] = 0;
    for (int i = n-1; i>=0; i--) {
        int lim = min(K, n-i);
        for (int c = lim; c >= 1; c--) // backwards so f[c-1] is still the old value
            if (f[c-1] != -inf)
                f[c] = max(f[c], f[c-1] + p[i] - c * m[i]);
    }

    cout << *max_element(f,f+K+1);

}
int main() {
    init_code();
    int t=1;
    // cin >> t;
    while (t--) {
        solve();
    }
    
}