Submission #644978

#	Time	Username	Problem	Language	Result	Execution time	Memory
644978		ghostwriter	Boat (APIO16_boat)	C++14	0 / 100	257 ms	2304 KiB

boat

#include <bits/stdc++.h>
using namespace std;
#ifdef LOCAL
#include <debug.h>
#endif
#define ft front
#define bk back
#define st first
#define nd second
#define ins insert
#define ers erase
#define pb push_back
#define pf push_front
#define _pb pop_back
#define _pf pop_front
#define lb lower_bound
#define ub upper_bound
#define mtp make_tuple
#define bg begin
#define ed end
#define all(x) (x).bg(), (x).ed()
#define sz(x) (int)(x).size()
typedef long long ll; typedef unsigned long long ull;
typedef double db; typedef long double ldb;
typedef pair<int, int> pi; typedef pair<ll, ll> pll;
typedef vector<int> vi; typedef vector<ll> vll; typedef vector<pi> vpi; typedef vector<pll> vpll;
typedef string str;
template<typename T> T gcd(T a, T b) { return (b == 0? a : gcd(b, a % b)); }
template<typename T> T lcm(T a, T b) { return a / gcd(a, b) * b; }
#define FOR(i, l, r) for (int (i) = (l); (i) <= (r); ++(i))
#define FOS(i, r, l) for (int (i) = (r); (i) >= (l); --(i))
#define FRN(i, n) for (int (i) = 0; (i) < (n); ++(i))
#define FSN(i, n) for (int (i) = (n) - 1; (i) >= 0; --(i))
#define EACH(i, x) for (auto &(i) : (x))
#define WHILE while
#define file "TEST"
mt19937 rd(chrono::steady_clock::now().time_since_epoch().count());
ll rand(ll l, ll r) { return uniform_int_distribution<ll>(l, r)(rd); }
/*
----------------------------------------------------------------
    END OF TEMPLATE
----------------------------------------------------------------
    Tran The Bao - ghostwriter
    Training for VOI23 gold medal
----------------------------------------------------------------
    DIT ME CHUYEN BAO LOC
----------------------------------------------------------------
*/
const int M = 1e9 + 7;
const int N = 505;
int n, a[N], b[N], a1[N], b1[N], d[N][N], d1[N][N], rs = 1;
signed main() {
    ios_base::sync_with_stdio(0), cin.tie(0), cout.tie(0);
    // freopen(file".inp", "r", stdin);
    // freopen(file".out", "w", stdout);
    cin >> n;
    FOR(i, 1, n) cin >> a[i] >> b[i];
    FOR(i, 1, n)
    FOR(j, i, n) {
    	FOR(z, i, j) {
    		a1[z] = a[z];
    		b1[z] = b[z];
    	}
    	FOR(z, i + 1, j) b1[z] = min(b1[z], b1[z - 1]);
    	FOS(z, j - 1, i) a1[z] = max(a1[z], a1[z + 1]);
    	bool ok = 1;
    	FOR(z, i, j)
    		if (a1[z] > b1[z])
    			ok = 0;
    	if (!ok) continue;
    	d1[i][j] = 1;
    	FOR(z, i, j) d1[i][j] = 1LL * d1[i][j] * (b1[z] - a1[z] + 1) % M;
    }
    d[n + 1][0] = 1;
    FOS(i, n, 1)
    FOS(j, n - i, 0) {
    	d[i][j] = 1LL * (b[i] - a[i] + 2) * d[i + 1][j] % M;
    	FOR(z, 1, j) {
    		if (i + z > n) break;
    		d[i][j] = (d[i][j] + 1LL * d1[i][z] * d[i + z + 1][j - z] % M) % M;
    	}
    }
    FOR(i, 1, n) rs = 1LL * rs * (b[i] - a[i] + 2) % M;
    FOR(i, 1, n - 1)
    	if (i & 1) rs = (rs - d[1][i] + M) % M;
    	else rs = (rs + d[1][i]) % M;
    cout << rs;
    return 0;
}
/*
2
1 2
2 3
----------------------------------------------------------------
From Benq:
    stuff you should look for
        * int overflow, array bounds
        * special cases (n=1?)
        * do smth instead of nothing and stay organized
        * WRITE STUFF DOWN
        * DON'T GET STUCK ON ONE APPROACH
----------------------------------------------------------------
*/

Compilation message (stderr)

boat.cpp: In function 'int main()':
boat.cpp:30:31: warning: unnecessary parentheses in declaration of 'i' [-Wparentheses]
   30 | #define FOR(i, l, r) for (int (i) = (l); (i) <= (r); ++(i))
      |                               ^
boat.cpp:57:5: note: in expansion of macro 'FOR'
   57 |     FOR(i, 1, n) cin >> a[i] >> b[i];
      |     ^~~
boat.cpp:30:31: warning: unnecessary parentheses in declaration of 'i' [-Wparentheses]
   30 | #define FOR(i, l, r) for (int (i) = (l); (i) <= (r); ++(i))
      |                               ^
boat.cpp:58:5: note: in expansion of macro 'FOR'
   58 |     FOR(i, 1, n)
      |     ^~~
boat.cpp:30:31: warning: unnecessary parentheses in declaration of 'j' [-Wparentheses]
   30 | #define FOR(i, l, r) for (int (i) = (l); (i) <= (r); ++(i))
      |                               ^
boat.cpp:59:5: note: in expansion of macro 'FOR'
   59 |     FOR(j, i, n) {
      |     ^~~
boat.cpp:30:31: warning: unnecessary parentheses in declaration of 'z' [-Wparentheses]
   30 | #define FOR(i, l, r) for (int (i) = (l); (i) <= (r); ++(i))
      |                               ^
boat.cpp:60:6: note: in expansion of macro 'FOR'
   60 |      FOR(z, i, j) {
      |      ^~~
boat.cpp:30:31: warning: unnecessary parentheses in declaration of 'z' [-Wparentheses]
   30 | #define FOR(i, l, r) for (int (i) = (l); (i) <= (r); ++(i))
      |                               ^
boat.cpp:64:6: note: in expansion of macro 'FOR'
   64 |      FOR(z, i + 1, j) b1[z] = min(b1[z], b1[z - 1]);
      |      ^~~
boat.cpp:31:31: warning: unnecessary parentheses in declaration of 'z' [-Wparentheses]
   31 | #define FOS(i, r, l) for (int (i) = (r); (i) >= (l); --(i))
      |                               ^
boat.cpp:65:6: note: in expansion of macro 'FOS'
   65 |      FOS(z, j - 1, i) a1[z] = max(a1[z], a1[z + 1]);
      |      ^~~
boat.cpp:30:31: warning: unnecessary parentheses in declaration of 'z' [-Wparentheses]
   30 | #define FOR(i, l, r) for (int (i) = (l); (i) <= (r); ++(i))
      |                               ^
boat.cpp:67:6: note: in expansion of macro 'FOR'
   67 |      FOR(z, i, j)
      |      ^~~
boat.cpp:30:31: warning: unnecessary parentheses in declaration of 'z' [-Wparentheses]
   30 | #define FOR(i, l, r) for (int (i) = (l); (i) <= (r); ++(i))
      |                               ^
boat.cpp:72:6: note: in expansion of macro 'FOR'
   72 |      FOR(z, i, j) d1[i][j] = 1LL * d1[i][j] * (b1[z] - a1[z] + 1) % M;
      |      ^~~
boat.cpp:31:31: warning: unnecessary parentheses in declaration of 'i' [-Wparentheses]
   31 | #define FOS(i, r, l) for (int (i) = (r); (i) >= (l); --(i))
      |                               ^
boat.cpp:75:5: note: in expansion of macro 'FOS'
   75 |     FOS(i, n, 1)
      |     ^~~
boat.cpp:31:31: warning: unnecessary parentheses in declaration of 'j' [-Wparentheses]
   31 | #define FOS(i, r, l) for (int (i) = (r); (i) >= (l); --(i))
      |                               ^
boat.cpp:76:5: note: in expansion of macro 'FOS'
   76 |     FOS(j, n - i, 0) {
      |     ^~~
boat.cpp:30:31: warning: unnecessary parentheses in declaration of 'z' [-Wparentheses]
   30 | #define FOR(i, l, r) for (int (i) = (l); (i) <= (r); ++(i))
      |                               ^
boat.cpp:78:6: note: in expansion of macro 'FOR'
   78 |      FOR(z, 1, j) {
      |      ^~~
boat.cpp:30:31: warning: unnecessary parentheses in declaration of 'i' [-Wparentheses]
   30 | #define FOR(i, l, r) for (int (i) = (l); (i) <= (r); ++(i))
      |                               ^
boat.cpp:83:5: note: in expansion of macro 'FOR'
   83 |     FOR(i, 1, n) rs = 1LL * rs * (b[i] - a[i] + 2) % M;
      |     ^~~
boat.cpp:30:31: warning: unnecessary parentheses in declaration of 'i' [-Wparentheses]
   30 | #define FOR(i, l, r) for (int (i) = (l); (i) <= (r); ++(i))
      |                               ^
boat.cpp:84:5: note: in expansion of macro 'FOR'
   84 |     FOR(i, 1, n - 1)
      |     ^~~

• Subtask 1: 0 / 9
• Subtask 2: 0 / 22
• Subtask 3: 0 / 27
• Subtask 4: 0 / 42