Problem p02706 (C++) — buggy submission, verdict: Runtime Error

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
using namespace std;

#define ff first1
#define ss second
#define int long long
#define pb push_back
#define mp make_pair
#define set set<string> // insert()
#define pii pair<int, int>
#define vi vector<int>
#define mii map<int, int>
#define pqb priority_queue<int>
#define pqs priority_queue<int, vi, greater<int>>
#define setbits(x) __builtin_popcountll(x)
#define zrobits(x) __builtin_ctzll(x)
#define mod 1000000007
#define inf 1e18
#define ps(x, y) fixed << setprecision(y) << x
#define mk(arr, n, type) type *arr = new type[n];
#define w(x)                                                                   \\
  int x;                                                                       \\
  cin >> x;                                                                    \\
  while (x--)
#define FIO                                                                    \\
  ios_base::sync_with_stdio(0);                                                \\
  cin.tie(0);                                                                  \\
  cout.tie(0)
// mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

typedef tree<int, null_type, less<int>, rb_tree_tag,
             tree_order_statistics_node_update>
    pbds;

int32_t main() {
  int v;
  cin >> v;
  int n;
  cin >> n;
  mk(a, n, int);
  int sum = 0;
  for (int i = 0; i < n; i++) {
    cin >> a[i];
    sum += a[i];
  }
  if (sum <= v)
    cout << v - sum;
  else
    cout << "-1";

  return 0;
}


Error: -6
terminate called after throwing an instance of 'std::bad_alloc'
  what():  std::bad_alloc


Fixed submission:

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
using namespace std;

#define ff first1
#define ss second
#define int long long
#define pb push_back
#define mp make_pair
#define set set<string> // insert()
#define pii pair<int, int>
#define vi vector<int>
#define mii map<int, int>
#define pqb priority_queue<int>
#define pqs priority_queue<int, vi, greater<int>>
#define setbits(x) __builtin_popcountll(x)
#define zrobits(x) __builtin_ctzll(x)
#define mod 1000000007
#define inf 1e18
#define ps(x, y) fixed << setprecision(y) << x
#define mk(arr, n, type) type *arr = new type[n];
#define w(x)                                                                   \\
  int x;                                                                       \\
  cin >> x;                                                                    \\
  while (x--)
#define FIO                                                                    \\
  ios_base::sync_with_stdio(0);                                                \\
  cin.tie(0);                                                                  \\
  cout.tie(0)
// mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

typedef tree<int, null_type, less<int>, rb_tree_tag,
             tree_order_statistics_node_update>
    pbds;

int32_t main() {
  int v;
  cin >> v;
  int n;
  mk(a, n, int);
  int sum = 0;
  cin >> n;
  for (int i = 0; i < n; i++) {
    cin >> a[i];
    sum += a[i];
  }
  if (sum <= v)
    cout << v - sum;
  else
    cout << "-1";

  return 0;
}