Submission #550396

# Submission time Handle Problem Language Result Execution time Memory
550396 2022-04-18T03:52:17 Z farhan132 Boat (APIO16_boat) C++17
27 / 100
2000 ms 5128 KB
/***Farhan132***/
//#pragma GCC optimize("Ofast")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,avx2,fma")
//#pragma GCC optimization ("unroll-loops")
//#pragma GCC optimize("Ofast,fast-math")
 
 
#include <bits/stdc++.h>
 
 
 
using namespace std;
 
typedef long long ll;
typedef unsigned long long ull;
typedef double dd;
typedef vector<ll> vll;
typedef pair<ll , ll> ii;
typedef vector< ii > vii;
typedef pair < pair < ll , ll > , pair < ll , ll > > cm; 
typedef tuple < ll,  ll, ll > tp;
 
#define ff first
#define ss second
#define pb push_back
#define in insert
#define f0(b) for(int i=0;i<(b);i++)
#define f00(b) for(int j=0;j<(b);j++)
#define f1(b) for(int i=1;i<=(b);i++)
#define f11(b) for(int j=1;j<=(b);j++)
#define f2(a,b) for(int i=(a);i<=(b);i++)
#define f22(a,b) for(int j=(a);j<=(b);j++)
#define sf(a) scanf("%lld",&a)
#define sff(a,b) scanf("%lld %lld", &a , &b)
#define pf(a) printf("%lld\n",a)
#define pff(a,b) printf("%lld %lld\n", a , b)
#define bug printf("**!\n")
#define mem(a , b) memset(a, b ,sizeof(a))
#define front_zero(n) __builtin_clzll(n)
#define back_zero(n) __builtin_ctzll(n)
#define total_one(n) __builtin_popcount(n)
#define clean fflush(stdout)
 
//const ll mod =  (ll) 998244353;
const ll mod =  (ll) 1e9 + 7;
const ll maxn = (ll)1e8 + 5;
const int nnn = 1048590;
const int inf = numeric_limits<int>::max()-1;
//const ll INF = numeric_limits<ll>::max()-1;
const ll INF = (ll)1e18;
 
ll dx[]={0,1,0,-1};
ll dy[]={1,0,-1,0};
ll dxx[]={0,1,0,-1,1,1,-1,-1};
ll dyy[]={1,0,-1,0,1,-1,1,-1};
 
bool USACO = 0;
 
mt19937 rng(chrono::system_clock::now().time_since_epoch().count());
 
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
 
template <typename T> using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;

const ll N = 505;

ll fac[N];
 
void pre(ll n){
    fac[0] = 1;
    for(ll i = 1; i < n; i++){
        fac[i] = (fac[i-1] * i)%mod;
    }
    return;
}
ll pw(ll a , ll b){
    ll res = 1;
    while(b){
        if(b&1) res = (res*a)%mod;
        a = (a*a)%mod;
        b /= 2;
    }
    return res;
}
 
ll nCr(ll n , ll r){
    if(n == r) return 1;
    if(n < r) return 0;
    ll ans = fac[n] * (pw(fac[r] , mod-2));
    ans %= mod;
    ans *= pw(fac[n-r] , mod-2);
    return ans%mod;
}


ll dp[N][2*N];
ll combo[2*N][N];
ll a[N] , b[N];

void solve(){
  
  ll n; cin >> n;
  vector < ll > idx; idx.pb(0); idx.pb(1);
  for(ll i = 1; i <= n; i++){
    cin >> a[i] >> b[i];
    idx.pb(a[i]); idx.pb(b[i] + 1);
  }
  sort(idx.begin(), idx.end());
  idx.erase(unique(idx.begin(), idx.end()), idx.end());

  mem(dp, 0);
  ll sz = idx.size();

  for(ll i = 0; i < sz - 1; i++){
    ll len = idx[i + 1] - idx[i];
    for(ll j = 0; j <= n; j++){
       combo[i][j] = 0;
       ll res = 1, l = len;
       for(ll x = 1; x <= j; x++){
        res = (res * l)%mod; l--;
        res = (res * pw(x , mod - 2))%mod;
        combo[i][j] += nCr(j - 1, x - 1) * res;
        combo[i][j] %= mod;
       }
    }
  }

  for(ll i = 0; i < sz; i++) dp[0][i] = 1;
  ll ans = 0;
  
  for(ll i = 1; i <= n; i++){
    a[i] = lower_bound(idx.begin(), idx.end(), a[i]) - idx.begin();
    b[i] = upper_bound(idx.begin(), idx.end(), b[i]) - idx.begin() - 1;
    dp[i][0] = 0;
    for(ll x = a[i]; x <= b[i]; x++){
        ll cnt = 1;
        ll len = idx[x + 1] - idx[x];
        for(ll j = i - 1; j >= 0; j--){
            dp[i][x] += combo[x][cnt] * dp[j][x - 1];
            dp[i][x] %= mod;
            if(a[j] <= x && b[j] >= x) cnt++;
        }
    }
    for(ll x = 1; x < sz; x++) dp[i][x] = (dp[i][x - 1] + dp[i][x])%mod;
    ans += dp[i][sz-1];
  }
  cout << ans%mod << '\n';


  return;
}
 
int main() {
    
    
    #ifdef LOCAL
        freopen("in", "r", stdin);
        freopen("out", "w", stdout);
        auto start_time = clock();
    #else 
       ios_base::sync_with_stdio(0); cin.tie(NULL); cout.tie(NULL);
    #endif
 
    pre(N);
 
    ll T = 1, CT = 0;  //cin >> T; 
 
    while(T--){
       //  cout << "Case #" << ++CT <<": " ;
        solve();
    }
    #ifdef LOCAL
        auto end_time = clock();
        cerr<< "Execution time: "<<(end_time - start_time)*(int)1e3/CLOCKS_PER_SEC<<" ms\n";
    #endif
 
    return 0;
}

Compilation message

boat.cpp: In function 'void solve()':
boat.cpp:139:12: warning: unused variable 'len' [-Wunused-variable]
  139 |         ll len = idx[x + 1] - idx[x];
      |            ^~~
boat.cpp: In function 'int main()':
boat.cpp:168:15: warning: unused variable 'CT' [-Wunused-variable]
  168 |     ll T = 1, CT = 0;  //cin >> T;
      |               ^~
# Verdict Execution time Memory Grader output
1 Execution timed out 2077 ms 4440 KB Time limit exceeded
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Execution timed out 2077 ms 4440 KB Time limit exceeded
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 408 ms 5100 KB Output is correct
2 Correct 405 ms 5084 KB Output is correct
3 Correct 408 ms 5056 KB Output is correct
4 Correct 397 ms 5024 KB Output is correct
5 Correct 413 ms 5112 KB Output is correct
6 Correct 408 ms 5040 KB Output is correct
7 Correct 405 ms 5128 KB Output is correct
8 Correct 394 ms 5120 KB Output is correct
9 Correct 414 ms 5060 KB Output is correct
10 Correct 402 ms 5056 KB Output is correct
11 Correct 401 ms 5120 KB Output is correct
12 Correct 402 ms 5072 KB Output is correct
13 Correct 401 ms 5124 KB Output is correct
14 Correct 400 ms 5068 KB Output is correct
15 Correct 400 ms 5068 KB Output is correct
16 Correct 235 ms 4676 KB Output is correct
17 Correct 229 ms 4776 KB Output is correct
18 Correct 231 ms 4784 KB Output is correct
19 Correct 232 ms 4740 KB Output is correct
20 Correct 226 ms 4736 KB Output is correct
# Verdict Execution time Memory Grader output
1 Execution timed out 2077 ms 4440 KB Time limit exceeded
2 Halted 0 ms 0 KB -