Submission #257297

#	Time	Username	Problem	Language	Result	Execution time	Memory
257297		BThero	Intergalactic ship (IZhO19_xorsum)	C++17	17 / 100	2086 ms	384 KiB

xorsum

// chrono::system_clock::now().time_since_epoch().count()
#include<bits/stdc++.h>

#define pb push_back
#define eb emplace_back
#define mp make_pair
#define fi first
#define se second
#define all(x) (x).begin(), (x).end()
#define debug(x) cerr << #x << " = " << x << endl;

using namespace std;

typedef long long ll;
typedef pair<int, int> pii;

const int MAXN = (int)1e3 + 5;
const int MOD = (int)1e9 + 7;

array<int, 3> que[MAXN];
int dp[2][2], ndp[2][2];
int arr[MAXN];
int n, q, ans;

int addMod(int a, int b, int m = MOD) {
  a += b;
  
  if (m <= a) {
    a -= m;
  }
  
  return a;
}

int mulMod(int a, int b, int m = MOD) {
  return a * 1ll * b % m;
}

int bit(int x, int p) {
  return (x >> p) & 1;
}

void solve() {
  scanf("%d", &n);
  
  for (int i = 1; i <= n; ++i) {
    scanf("%d", &arr[i]);
  }
  
  scanf("%d", &q);
  
  for (int i = 1; i <= q; ++i) {
    int l, r, x;
    scanf("%d %d %d", &l, &r, &x);
    que[i] = {l, r, x};
  }
  
  for (int i = 1; i <= n; ++i) {
    for (int j = 1; j <= n; ++j) {
      int cur = 0;
    
      for (int b1 = 0; b1 < 7; ++b1) {
        for (int b2 = 0; b2 < 7; ++b2) {
          for (int x = 0; x < 2; ++x) {
            for (int y = 0; y < 2; ++y) {
              dp[x][y] = ndp[x][y] = 0;
            }
          }
          
          dp[bit(arr[i], b1)][bit(arr[j], b2)] = 1;
          
          for (int k = 1; k <= q; ++k) {
            auto &[l, r, t] = que[k];
            
            for (int x = 0; x < 2; ++x) {
              for (int y = 0; y < 2; ++y) {
                ndp[x][y] = addMod(ndp[x][y], dp[x][y]);
                int nx = x, ny = y;
                
                if (l <= i && i <= r) {
                  nx ^= bit(t, b1);
                }
                
                if (l <= j && j <= r) {
                  ny ^= bit(t, b2);
                }
                
                ndp[nx][ny] = addMod(ndp[nx][ny], dp[x][y]);
              }
            }
            
            for (int x = 0; x < 2; ++x) {
              for (int y = 0; y < 2; ++y) {
                dp[x][y] = ndp[x][y];
                ndp[x][y] = 0;
              }
            }
          }
          
          cur = addMod(cur, mulMod(dp[1][1], (1 << (b1 + b2))));
        }
      }
      
      ans = addMod(ans, mulMod(cur, mulMod(min(i, j), n - max(i, j) + 1)));
    }
  }
  
  printf("%d\n", ans);
}

int main() {
  int tt = 1;
  
  while (tt--) {
    solve();
  }

  return 0;
}

Compilation message (stderr)

xorsum.cpp: In function 'void solve()':
xorsum.cpp:44:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d", &n);
   ~~~~~^~~~~~~~~~
xorsum.cpp:47:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d", &arr[i]);
     ~~~~~^~~~~~~~~~~~~~~
xorsum.cpp:50:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d", &q);
   ~~~~~^~~~~~~~~~
xorsum.cpp:54:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d %d %d", &l, &r, &x);
     ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~

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