oj.uz

Submission #699554

# Submission time Handle Problem Language Result Execution time Memory
699554 2023-02-17T11:50:10 Z Abrar_Al_Samit Boat (APIO16_boat) C++17
9 / 100
 2000 ms 3284 KB 
#include<bits/stdc++.h>
using namespace std;

const int nax = 503;
const int mod = 1e9 + 7;

vector<int>ind[nax*2];
int a[nax], b[nax];
int n, m;
int dp[nax*2][nax];
vector<int>imp;

int add(int a, int b) {
  a += b;
  if(a>=mod) a -= mod;
  return a;
}
int mul(int a, int b) {
  return (a * 1LL * b) % mod;
}
int quickpow(int a, int b) {
  int ret = 1;
  while(b) {
    if(b&1) ret = mul(ret, a);
    a = mul(a, a);
    b >>= 1;
  }
  return ret;
}

int C(int n, int r) {
  int ret = 1;
  for(int i=n-r+1; i<=n; ++i) {
    ret = mul(ret, i);
  }
  for(int i=1; i<=r; ++i) {
    ret = mul(ret, quickpow(i, mod-2));
  }
  return ret;
}
int solve(int i, int prv) {
  if(i==m-1) return prv>0;
  int &ret = dp[i][prv];
  if(ret!=-1) return ret;
  ret = 0;

  ret = solve(i+1, prv);
  int len = imp[i+1]-imp[i];

  for(int mx=0, cur_op=0; mx<ind[i].size(); ++mx) {
    if(ind[i][mx]<=prv) continue;

    int cur = solve(i+1, ind[i][mx]);
    for(int take=0; take<=min(cur_op, len-1); ++take) {
      ret = add(ret, mul(cur, mul(C(cur_op, take), C(len, take+1))));
    }
    cur_op++;
  }
  return ret;
}
void PlayGround() {
  cin>>n;
  set<int>pts;
  for(int i=1; i<=n; ++i) {
    cin>>a[i]>>b[i];
    pts.insert(a[i]);
    pts.insert(b[i]+1);
  }

  for(int x : pts) {
    imp.push_back(x);
  } 
  m = imp.size();
  for(int i=0; i<m; ++i) {
    for(int j=1; j<=n; ++j) {
      if(imp[i]>=a[j] && imp[i]<=b[j]) {
        ind[i].push_back(j);
      }
    }
  }
  // for(int i=0; i<m; ++i) {
  //   cerr<<imp[i]<<' ';
  // } cerr<<endl;
  memset(dp, -1, sizeof dp);
  cout<<solve(0, 0)<<'\n';


  // cerr << "Time elapsed: " << 1.0 * clock() / CLOCKS_PER_SEC << " s.\n";
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  PlayGround();
  return 0;
}

Compilation message

boat.cpp: In function 'int solve(int, int)':
boat.cpp:50:29: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   50 |   for(int mx=0, cur_op=0; mx<ind[i].size(); ++mx) {
      |                           ~~^~~~~~~~~~~~~~

Subtask #1
9.0 / 9.0

# Verdict Execution time Memory Grader output
1 Correct 21 ms 2516 KB Output is correct
2 Correct 17 ms 2544 KB Output is correct
3 Correct 20 ms 2540 KB Output is correct
4 Correct 17 ms 2544 KB Output is correct
5 Correct 18 ms 2544 KB Output is correct
6 Correct 29 ms 2528 KB Output is correct
7 Correct 26 ms 2516 KB Output is correct
8 Correct 27 ms 2516 KB Output is correct
9 Correct 26 ms 2516 KB Output is correct
10 Correct 26 ms 2516 KB Output is correct
11 Correct 27 ms 2516 KB Output is correct
12 Correct 27 ms 2516 KB Output is correct
13 Correct 28 ms 2516 KB Output is correct
14 Correct 26 ms 2536 KB Output is correct
15 Correct 26 ms 2516 KB Output is correct
16 Correct 13 ms 2260 KB Output is correct
17 Correct 14 ms 2280 KB Output is correct
18 Correct 13 ms 2376 KB Output is correct
19 Correct 14 ms 2384 KB Output is correct
20 Correct 14 ms 2260 KB Output is correct

Subtask #2
0 / 22.0

# Verdict Execution time Memory Grader output
1 Correct 21 ms 2516 KB Output is correct
2 Correct 17 ms 2544 KB Output is correct
3 Correct 20 ms 2540 KB Output is correct
4 Correct 17 ms 2544 KB Output is correct
5 Correct 18 ms 2544 KB Output is correct
6 Correct 29 ms 2528 KB Output is correct
7 Correct 26 ms 2516 KB Output is correct
8 Correct 27 ms 2516 KB Output is correct
9 Correct 26 ms 2516 KB Output is correct
10 Correct 26 ms 2516 KB Output is correct
11 Correct 27 ms 2516 KB Output is correct
12 Correct 27 ms 2516 KB Output is correct
13 Correct 28 ms 2516 KB Output is correct
14 Correct 26 ms 2536 KB Output is correct
15 Correct 26 ms 2516 KB Output is correct
16 Correct 13 ms 2260 KB Output is correct
17 Correct 14 ms 2280 KB Output is correct
18 Correct 13 ms 2376 KB Output is correct
19 Correct 14 ms 2384 KB Output is correct
20 Correct 14 ms 2260 KB Output is correct
21 Execution timed out 2064 ms 3284 KB Time limit exceeded
22 Halted 0 ms 0 KB -

Subtask #3
0 / 27.0

# Verdict Execution time Memory Grader output
1 Execution timed out 2036 ms 2388 KB Time limit exceeded
2 Halted 0 ms 0 KB -

Subtask #4
0 / 42.0

# Verdict Execution time Memory Grader output
1 Correct 21 ms 2516 KB Output is correct
2 Correct 17 ms 2544 KB Output is correct
3 Correct 20 ms 2540 KB Output is correct
4 Correct 17 ms 2544 KB Output is correct
5 Correct 18 ms 2544 KB Output is correct
6 Correct 29 ms 2528 KB Output is correct
7 Correct 26 ms 2516 KB Output is correct
8 Correct 27 ms 2516 KB Output is correct
9 Correct 26 ms 2516 KB Output is correct
10 Correct 26 ms 2516 KB Output is correct
11 Correct 27 ms 2516 KB Output is correct
12 Correct 27 ms 2516 KB Output is correct
13 Correct 28 ms 2516 KB Output is correct
14 Correct 26 ms 2536 KB Output is correct
15 Correct 26 ms 2516 KB Output is correct
16 Correct 13 ms 2260 KB Output is correct
17 Correct 14 ms 2280 KB Output is correct
18 Correct 13 ms 2376 KB Output is correct
19 Correct 14 ms 2384 KB Output is correct
20 Correct 14 ms 2260 KB Output is correct
21 Execution timed out 2064 ms 3284 KB Time limit exceeded
22 Halted 0 ms 0 KB -