제출 #646257

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
646257		ghostwriter	건물 4 (JOI20_building4)	C++14	100 / 100	346 ms	75576 KiB

building4

#include <bits/stdc++.h>
using namespace std;
#ifdef LOCAL
#include <debug.h>
#else
#define debug(...)
#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 oo = 1e9 + 5;
const int N = 1e6 + 5;
int n, a[N], b[N];
pi d[N][2];
void trace(int i, bool z, int j) {
	if (i == 0) return;
	int nxta = (z? b[i + 1] : a[i + 1]);
	if (a[i] <= nxta && d[i - 1][0].st <= j - 1 && j - 1 <= d[i - 1][0].nd) {
		trace(i - 1, 0, j - 1);
		cout << 'A';
		return;
	}
	trace(i - 1, 1, j);
	cout << 'B';
}
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, 2 * n) cin >> a[i];
    FOR(i, 1, 2 * n) cin >> b[i];
    a[2 * n + 1] = b[2 * n + 1] = oo;
    d[0][0] = d[0][1] = {0, 0};
    FOR(i, 1, 2 * n)
    FOR(j, 0, 1) {
    	int nxta = (j? b[i + 1] : a[i + 1]);
    	d[i][j] = {oo, -oo};
    	if (a[i] <= nxta) {
    		d[i][j].st = min(d[i][j].st, d[i - 1][0].st + 1);
    		d[i][j].nd = max(d[i][j].nd, d[i - 1][0].nd + 1);
    	}
    	if (b[i] <= nxta) {
    		d[i][j].st = min(d[i][j].st, d[i - 1][1].st);
    		d[i][j].nd = max(d[i][j].nd, d[i - 1][1].nd);	
    	}
    }
    if (d[2 * n][0].nd < n || d[2 * n][0].st > n) {
    	cout << -1;
    	return 0;
    }
    trace(2 * n, 0, n);
    return 0;
}
/*
1
2 2
2 2
----------------------------------------------------------------
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
----------------------------------------------------------------
*/

컴파일 시 표준 에러 (stderr) 메시지

building4.cpp: In function 'int main()':
building4.cpp:32:31: warning: unnecessary parentheses in declaration of 'i' [-Wparentheses]
   32 | #define FOR(i, l, r) for (int (i) = (l); (i) <= (r); ++(i))
      |                               ^
building4.cpp:71:5: note: in expansion of macro 'FOR'
   71 |     FOR(i, 1, 2 * n) cin >> a[i];
      |     ^~~
building4.cpp:32:31: warning: unnecessary parentheses in declaration of 'i' [-Wparentheses]
   32 | #define FOR(i, l, r) for (int (i) = (l); (i) <= (r); ++(i))
      |                               ^
building4.cpp:72:5: note: in expansion of macro 'FOR'
   72 |     FOR(i, 1, 2 * n) cin >> b[i];
      |     ^~~
building4.cpp:32:31: warning: unnecessary parentheses in declaration of 'i' [-Wparentheses]
   32 | #define FOR(i, l, r) for (int (i) = (l); (i) <= (r); ++(i))
      |                               ^
building4.cpp:75:5: note: in expansion of macro 'FOR'
   75 |     FOR(i, 1, 2 * n)
      |     ^~~
building4.cpp:32:31: warning: unnecessary parentheses in declaration of 'j' [-Wparentheses]
   32 | #define FOR(i, l, r) for (int (i) = (l); (i) <= (r); ++(i))
      |                               ^
building4.cpp:76:5: note: in expansion of macro 'FOR'
   76 |     FOR(j, 0, 1) {
      |     ^~~

• Subtask 1: 11 / 11
• Subtask 2: 89 / 89