Cod sursa(job #2798481)

Utilizator iancupoppPopp Iancu Alexandru iancupopp Data 11 noiembrie 2021 12:39:30
Problema Semne Scor 100
Compilator cpp-64 Status done
Runda Arhiva de probleme Marime 0.96 kb
#include <fstream>
#include <ctime>
#include <algorithm>

using namespace std;

const int N = 5e4 + 5;

int v[N], a[N], b[N];
char ans[N];

int main() {
  ios_base::sync_with_stdio(false);
  ifstream cin("semne.in");
  ofstream cout("semne.out");
  cin.tie(nullptr), cout.tie(nullptr);
  srand(time(nullptr));
  int n;
  long long s, sa, sb, sza, szb;
  cin >> n >> s;
  sa = sb = sza = szb = 0;
  for (int i = 0; i < n; ++i) {
    cin >> v[i];
    sa += v[i];
    a[sza++] = i;
  }
  random_shuffle(a, a + sza);
  while (sa - sb != s) {
    if (sa - sb > s) {
      int poz = rand() % sza;
      sa -= v[a[poz]], sb += v[a[poz]];
      b[szb++] = a[poz];
      a[poz] = a[--sza];
    } else {
      int poz = rand() % szb;
      sb -= v[b[poz]], sa += v[b[poz]];
      a[sza++] = b[poz];
      b[poz] = b[--szb];
    }
  }
  for (int i = 0; i < sza; ++i)
    ans[a[i]] = '+';
  for (int i = 0; i < szb; ++i)
    ans[b[i]] = '-';
  cout << ans << "\n";
  cout.close();
  return 0;
}