Submission #257301

#	Time	Username	Problem	Language	Result	Execution time	Memory
257301		BThero	Intergalactic ship (IZhO19_xorsum)	C++17	17 / 100	2093 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;
}

int calc(int p1, int p2) {
  int ret = 0;

  for (int a = 1; a <= n; ++a) {
    for (int b = 1; b <= n; ++b) {
      for (int x = 0; x < 2; ++x) {
        for (int y = 0; y < 2; ++y) {
          dp[x][y] = 0;
        }
      }
      
      dp[bit(arr[a], p1)][bit(arr[b], p2)] = 1;
      
      for (int i = 1; i <= q; ++i) {
        auto &[l, r, k] = que[i];
        
        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 <= a && a <= r) {
              nx ^= bit(k, p1);
            }
            
            if (l <= b && b <= r) {
              ny ^= bit(k, p2);
            }
            
            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;
          }
        }
      }
      
      ret = addMod(ret, mulMod(dp[1][1], mulMod(min(a, b), n - max(a, b) + 1)));
    }
  }
  
  return ret;
}

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 a = 0; a < 7; ++a) {
    for (int b = 0; b < 7; ++b) {
      ans = addMod(ans, mulMod(calc(a, b), (1 << (a + b))));
    }
  }
  
  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:92:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d", &n);
   ~~~~~^~~~~~~~~~
xorsum.cpp:95:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d", &arr[i]);
     ~~~~~^~~~~~~~~~~~~~~
xorsum.cpp:98:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d", &q);
   ~~~~~^~~~~~~~~~
xorsum.cpp:102:10: 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