Submission #905007

#	Time	Username	Problem	Language	Result	Execution time	Memory
905007		LucaLucaM	Intergalactic ship (IZhO19_xorsum)	C++17	0 / 100	2098 ms	2904 KiB

xorsum

#include <iostream>
#include <vector>
#include <algorithm>
#include <cassert>
#include <cstring>
#warning That's the baby, that's not my baby
#define int long long

typedef long long ll;

const int mod = 1e9 + 7;
const int NMAX = 30;
const int VMAX = 128;

struct Update {
  int l, r, x;
};

int cnt[VMAX][VMAX];
ll newCnt[VMAX][VMAX];
ll ways[NMAX][NMAX];

/// cnt[x][y] =def= pt cate subset uri am a[i] = x, a[j] = y?

#define debug(x) #x << " = " << x

signed main() {
  std::ios_base::sync_with_stdio(false);
  std::cin.tie(0);

  int n;
  std::cin >> n;
  std::vector<int> a(n);
  for (int i = 0; i < n; i++) {
    std::cin >> a[i];
  }

  for (int i = 0; i < n; i++) {
    for (int j = i; j < n; j++) {
      ways[i][j] = (i + 1) * (n - j);
    }
  }

  int q;
  std::cin >> q;

  std::vector<Update> Q(q);

  for (auto &[l, r, v] : Q) {
    std::cin >> l >> r >> v;
    --l, --r;
  }

  ll answer = 0;

  for (int i = 0; i < n; i++) {
    for (int j = i; j < n; j++) {
      memset(cnt, 0, sizeof(cnt));
      cnt[a[i]][a[j]] = 1;
      for (auto &[l, r, v] : Q) {
        for (int x = 0; x < VMAX; x++) {
          for (int y = 0; y < VMAX; y++) {
            int newX = x;
            int newY = y;
            if (l <= i <= r) {
              newX ^= v;
            }
            if (l <= j <= r) {
              newY ^= v;
            }
            newCnt[x][y] += cnt[x][y];
            newCnt[newX][newY] += cnt[x][y];
          }
        }
        for (int x = 0; x < VMAX; x++) {
          for (int y = 0; y < VMAX; y++) {
            cnt[x][y] = newCnt[x][y] % mod;
            newCnt[x][y] = 0;
          }
        }
      }
      for (int x = 0; x < VMAX; x++) {
        for (int y = 0; y < VMAX; y++) {
          if (i == j) {
            if (x == y) {
//              if (cnt[x][x] != 0) {
//                std::cout << "! " << x << ' ' << i << ' ' << cnt[x][x] << '\n';
//              }
              answer += (ll) cnt[x][x] * x % mod * x % mod * ways[i][j] % mod;
            }
          } else {
            answer += (ll) 2 * cnt[x][y] * x % mod * y % mod * ways[i][j] % mod;
          }
        }
      }
    }
  }

  std::cout << answer % mod;

  return 0;
}

Compilation message (stderr)

xorsum.cpp:6:2: warning: #warning That's the baby, that's not my baby [-Wcpp]
    6 | #warning That's the baby, that's not my baby
      |  ^~~~~~~
xorsum.cpp: In function 'int main()':
xorsum.cpp:65:19: warning: comparisons like 'X<=Y<=Z' do not have their mathematical meaning [-Wparentheses]
   65 |             if (l <= i <= r) {
      |                 ~~^~~~
xorsum.cpp:68:19: warning: comparisons like 'X<=Y<=Z' do not have their mathematical meaning [-Wparentheses]
   68 |             if (l <= j <= r) {
      |                 ~~^~~~

• Subtask 1: 0 / 4
• Subtask 2: 0 / 5
• Subtask 3: 0 / 6
• Subtask 4: 0 / 9
• Subtask 5: 0 / 8
• Subtask 6: 0 / 11
• Subtask 7: 0 / 19
• Subtask 8: 0 / 30
• Subtask 9: 0 / 8