oj.uz

Submission #44989

# Submission time Handle Problem Language Result Execution time Memory
44989 2018-04-10T09:45:27 Z OneSubmissionMan Boat (APIO16_boat) C++11
9 / 100
 213 ms 4696 KB 
# include <bits/stdc++.h>

# define x first    
# define y second
# define mp make_pair
// everything go according to my plan      
# define pb push_back
# define sz(a) (int)(a.size())
# define vec vector         
// shimkenttin kyzdary, dzyn, dzyn, dzyn...
# define y1    Y_U_NO_y1
# define left  Y_U_NO_left
# define right Y_U_NO_right  

using namespace std;

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

const int Mod = (int)1e9 + 7;
const int MX = 1073741822;
const ll MXLL = 4e18;
const int Sz = 1110111;
// a pinch of soul
inline void Read_rap () {
  ios_base :: sync_with_stdio(0);
  cin.tie(0); cout.tie(0);
}
inline void randomizer3000 () {
  unsigned int seed;
  asm ("rdtsc" : "=A"(seed));
  srand (seed);
}
void files (string problem) {   
  if (fopen ((problem + ".in").c_str(),"r")) {
    freopen ((problem + ".in").c_str(),"r",stdin);
    freopen ((problem + ".out").c_str(),"w",stdout);
  }
}
void localInput(const char in[] = "s") { 
  if (fopen (in, "r")) {
    freopen (in, "r", stdin);
  }
  else
    cerr << "Warning: Input file not found" << endl;
}    
const int N = 500 + 1;

int n;
    
map <int, vec<int> > add;

int dp[2*N][N], pref[2*N][N];      

void Add (int &a, int b) {  
  a += b;
  if (a > Mod)  a -= Mod;
}      
int binpow (ll a, int b) {
  int res = 1;
  while (b) {
    if (b & 1)
      res = (res * a) % Mod;
    b >>= 1;
    a = (a * a) % Mod;
  }   
  return res;
}           
int inv (int a) {
  return binpow (a, Mod-2);
}    
               
int main()
{
  # ifdef Local
    //localInput();
  # endif
  Read_rap();    

  cin >> n;
  for (int i = 1; i <= n; i++) {
    int a, b; cin >> a >> b;
    add[a].pb (i);     
    add[b + 1].pb (i);
  }        
  vec <int> len (1);
  vec <vec <int> > v(1);  
  set <int> s;
  for (auto x : add)
    len.pb (x.x), v.pb (x.y);

  for (int i = 1; i < sz(len) - 1; i++)
    len[i] = len[i + 1] - len[i];
  len.pop_back(); 
        
  for (int i = 0; i <= n; i++)
    pref[0][i] = 1;
       
  for (int t = 1; t < sz(len); t++) { 
    int seglen = len[t];              
    for (auto y : v[t]) {           
      if (s.count (y)) s.erase (y); else s.insert (y);
    }       
    static vec<int> id;
    id.clear();
    id = vec<int> (s.begin(), s.end());
   
    for (int i = 0; i < sz(id); i++) {
      if (seglen > 1) { 
        ll sum = 0;         
        ll C = seglen;
        for (int j = i+1; j < sz(id); j++) {
          int k = j - i + 1;    
          if (k <= seglen) {
            C = (C * (seglen - k + 1) % Mod * inv (k)) % Mod;
            sum = (sum + C) % Mod;
          }
          Add (dp[t][id[j]], sum * 1ll * pref[t - 1][id[i] - 1] % Mod);                                       
        }
      }                    
      Add (dp[t][id[i]], pref[t - 1][id[i] - 1] * 1ll * seglen % Mod);
    }               
    for (int i = 1; i <= n; i++)
      Add (dp[t][i], dp[t - 1][i]);

    pref[t][0] = 1;
    for (int i = 1; i <= n; i++)
      pref[t][i] = (pref[t][i - 1] + dp[t][i]) % Mod;
  }     
  int ans = pref[sz(len) - 1][n] - 1;
  if (ans < 0)  ans += Mod;

  cout << ans;

  return 0;
}






// Coded by Z..

Compilation message

boat.cpp: In function 'void files(std::__cxx11::string)':
boat.cpp:37:13: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
     freopen ((problem + ".in").c_str(),"r",stdin);
     ~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
boat.cpp:38:13: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
     freopen ((problem + ".out").c_str(),"w",stdout);
     ~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
boat.cpp: In function 'void localInput(const char*)':
boat.cpp:43:13: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
     freopen (in, "r", stdin);
     ~~~~~~~~^~~~~~~~~~~~~~~~

Subtask #1
9.0 / 9.0

# Verdict Execution time Memory Grader output
1 Correct 10 ms 4348 KB Output is correct
2 Correct 9 ms 4452 KB Output is correct
3 Correct 9 ms 4528 KB Output is correct
4 Correct 9 ms 4692 KB Output is correct
5 Correct 9 ms 4692 KB Output is correct
6 Correct 9 ms 4692 KB Output is correct
7 Correct 10 ms 4692 KB Output is correct
8 Correct 9 ms 4692 KB Output is correct
9 Correct 10 ms 4692 KB Output is correct
10 Correct 9 ms 4692 KB Output is correct
11 Correct 9 ms 4692 KB Output is correct
12 Correct 9 ms 4692 KB Output is correct
13 Correct 11 ms 4692 KB Output is correct
14 Correct 11 ms 4692 KB Output is correct
15 Correct 11 ms 4696 KB Output is correct
16 Correct 4 ms 4696 KB Output is correct
17 Correct 4 ms 4696 KB Output is correct
18 Correct 4 ms 4696 KB Output is correct
19 Correct 4 ms 4696 KB Output is correct
20 Correct 4 ms 4696 KB Output is correct

Subtask #2
0 / 22.0

# Verdict Execution time Memory Grader output
1 Correct 10 ms 4348 KB Output is correct
2 Correct 9 ms 4452 KB Output is correct
3 Correct 9 ms 4528 KB Output is correct
4 Correct 9 ms 4692 KB Output is correct
5 Correct 9 ms 4692 KB Output is correct
6 Correct 9 ms 4692 KB Output is correct
7 Correct 10 ms 4692 KB Output is correct
8 Correct 9 ms 4692 KB Output is correct
9 Correct 10 ms 4692 KB Output is correct
10 Correct 9 ms 4692 KB Output is correct
11 Correct 9 ms 4692 KB Output is correct
12 Correct 9 ms 4692 KB Output is correct
13 Correct 11 ms 4692 KB Output is correct
14 Correct 11 ms 4692 KB Output is correct
15 Correct 11 ms 4696 KB Output is correct
16 Correct 4 ms 4696 KB Output is correct
17 Correct 4 ms 4696 KB Output is correct
18 Correct 4 ms 4696 KB Output is correct
19 Correct 4 ms 4696 KB Output is correct
20 Correct 4 ms 4696 KB Output is correct
21 Incorrect 213 ms 4696 KB Output isn't correct
22 Halted 0 ms 0 KB -

Subtask #3
0 / 27.0

# Verdict Execution time Memory Grader output
1 Incorrect 27 ms 4696 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #4
0 / 42.0

# Verdict Execution time Memory Grader output
1 Correct 10 ms 4348 KB Output is correct
2 Correct 9 ms 4452 KB Output is correct
3 Correct 9 ms 4528 KB Output is correct
4 Correct 9 ms 4692 KB Output is correct
5 Correct 9 ms 4692 KB Output is correct
6 Correct 9 ms 4692 KB Output is correct
7 Correct 10 ms 4692 KB Output is correct
8 Correct 9 ms 4692 KB Output is correct
9 Correct 10 ms 4692 KB Output is correct
10 Correct 9 ms 4692 KB Output is correct
11 Correct 9 ms 4692 KB Output is correct
12 Correct 9 ms 4692 KB Output is correct
13 Correct 11 ms 4692 KB Output is correct
14 Correct 11 ms 4692 KB Output is correct
15 Correct 11 ms 4696 KB Output is correct
16 Correct 4 ms 4696 KB Output is correct
17 Correct 4 ms 4696 KB Output is correct
18 Correct 4 ms 4696 KB Output is correct
19 Correct 4 ms 4696 KB Output is correct
20 Correct 4 ms 4696 KB Output is correct
21 Incorrect 213 ms 4696 KB Output isn't correct
22 Halted 0 ms 0 KB -