Submission #378479

#	Time	Username	Problem	Language	Result	Execution time	Memory
378479		morato	Building 4 (JOI20_building4)	C++17	Compilation error	0 ms	0 KiB

building4

#include <bits/stdc++.h>
using namespace std;

const int MAXN = 2e3 + 5;
const long long INF = 1e18;

bool calculado[2 * MAXN][MAXN][2];
long long dp[2 * MAXN][MAXN][2];
long long a[2 * MAXN], b[2 * MAXN];

string ans;

int n;

long long solve(int i, int j, int f) {
	if (k > n || i - k > n || i > n + n) {
		// cout << i << ' ' << k << ' ' << n << '\n';
		return -INF;
	}
	if (i == n + n) {
		assert(k == n);
		return 0;
	}
	if (calculado[i][k][f]) {
		return dp[i][k][f];
	}
	calculado[i][k][f] = true;
	long long opcao1 = 0;
	long long opcao2 = 0;	
	if (i == 0) {
		opcao1 = a[i] + solve(i + 1, k + 1, 0);
		opcao2 = b[i] + solve(i + 1, k, 1);
		return dp[i][k][f] = max(opcao1, opcao2);
	}
	assert(i > 0);
	if (!f) {
		opcao1 = (a[i] >= a[i - 1] ? a[i] + solve(i + 1, k + 1, 0) : -INF);
		opcao2 = (b[i] >= a[i - 1] ? b[i] + solve(i + 1, k, 1) : -INF);
		return dp[i][k][f] = max(opcao1, opcao2);
	}
	opcao1 = (a[i] >= b[i - 1] ? a[i] + solve(i + 1, k + 1, 0) : -INF);
	opcao2 = (b[i] >= b[i - 1] ? b[i] + solve(i + 1, k, 1) : -INF);
	return dp[i][k][f] = max(opcao1, opcao2);
	
}

void recu(int i, int k, int f) {
	if (i == n + n) {
		return;
	}
	if (a[i] + solve(i + 1, k + 1, 0) > b[i] + solve(i + 1, k, 1)) {
		ans += 'A';
		recu(i + 1, k + 1, 0);
	} else {
		ans += 'B';
		recu(i + 1, k, 1);
	}
}

int main() {
	ios::sync_with_stdio(false);
	cin.tie(0);
	cin >> n;
	for (int i = 0; i < 2 * n; i++) {
		cin >> a[i];
	}
	for (int i = 0; i < 2 * n; i++) {
		cin >> b[i];
	}
	long long valor = solve(0, 0, 0);
	if (valor < 0) {
		cout << -1 << '\n';
	} else {
		recu(0, 0, 0);
		int cnta = 0;
		for (int i = 0; i < 2 * n; i++) 
			cnta += ans[i] == 'A';
		}
		assert(cnta == n);
		cout << ans << '\n';
	}
	return 0;
}

Compilation message (stderr)

building4.cpp: In function 'long long int solve(int, int, int)':
building4.cpp:16:6: error: 'k' was not declared in this scope
   16 |  if (k > n || i - k > n || i > n + n) {
      |      ^
In file included from /usr/include/c++/9/cassert:44,
                 from /usr/include/x86_64-linux-gnu/c++/9/bits/stdc++.h:33,
                 from building4.cpp:1:
building4.cpp:21:10: error: 'k' was not declared in this scope
   21 |   assert(k == n);
      |          ^
building4.cpp:24:19: error: 'k' was not declared in this scope
   24 |  if (calculado[i][k][f]) {
      |                   ^
building4.cpp:27:15: error: 'k' was not declared in this scope
   27 |  calculado[i][k][f] = true;
      |               ^
In file included from /usr/include/c++/9/cassert:44,
                 from /usr/include/x86_64-linux-gnu/c++/9/bits/stdc++.h:33,
                 from building4.cpp:1:
building4.cpp: In function 'int main()':
building4.cpp:79:10: error: 'cnta' was not declared in this scope
   79 |   assert(cnta == n);
      |          ^~~~
building4.cpp: At global scope:
building4.cpp:82:2: error: expected unqualified-id before 'return'
   82 |  return 0;
      |  ^~~~~~
building4.cpp:83:1: error: expected declaration before '}' token
   83 | }
      | ^