Submission #579206

#	Time	Username	Problem	Language	Result	Execution time	Memory
579206		cheissmart	Uplifting Excursion (BOI22_vault)	C++14	0 / 100	1 ms	468 KiB

vault

#include <bits/stdc++.h>
#define IO_OP std::ios::sync_with_stdio(0); std::cin.tie(0);
#define F first
#define S second
#define V vector
#define PB push_back
#define EB emplace_back
#define MP make_pair
#define SZ(v) int((v).size())
#define ALL(v) (v).begin(), (v).end()

using namespace std;

typedef long long ll;
typedef pair<int, int> pi;
typedef V<int> vi;

string _reset = "\u001b[0m", _yellow = "\u001b[33m", _bold = "\u001b[1m";
void DBG() { cerr << "]" << _reset << endl; }
template<class H, class...T> void DBG(H h, T ...t) {
	cerr << to_string(h);
	if(sizeof ...(t)) cerr << ", ";
	DBG(t...);
}
#ifdef CHEISSMART
#define debug(...) cerr << _yellow << _bold << "Line(" << __LINE__ << ") -> [" << #__VA_ARGS__ << "]: [", DBG(__VA_ARGS__)
#else
#define debug(...)
#endif

const int INF = 1e9 + 7, mxM = 101;

template<class T> void cmax(T& a, T b) { a = max(a, b); }

int m, l;
ll a[mxM * 2], b[mxM * 2];

signed main()
{
	IO_OP;

	cin >> m >> l;
	ll tot = 0, ans = 0;
	for(int i = -m; i <= m; i++) {
		cin >> a[i + m];
		tot += a[i + m] * i;
	}
	if(tot < l) {

		cout << "impossible\n";
		return 0;		
		tot = -tot;
		l = -l;
		for(int i = 0; i < m; i++)
			swap(a[i], a[2 * m - i]);
	}
	tot = 0;
	for(int i = -m; i <= 0; i++) {
		tot += a[i + m] * i;
		b[i + m] = a[i + m];
		ans += b[i + m];
	}

	if(tot > l) {
		cout << "impossible\n";
		return 0;
	}
	for(int i = 1; i <= m; i++) {
		assert(tot <= l);
		b[i + m] = min((l - tot) / i, a[i + m]);
		tot += b[i + m] * i;
		ans += b[i + m];
	}
	assert(tot <= l);
	assert(tot + mxM >= l);

	// int C = mxM * mxM * 2;
	// vi dp(C * 2, -INF);
	// dp[0 + C] = 0;

	// for(int i = -m; i <= m; i++) {
	// 	vi ndp(C * 2, -INF);
	// 	for(int delta = -2 * m; delta <= 2 * m; delta++) {
	// 		if(b[i + m] + delta < 0 || b[i + m] + delta > a[i + m]) continue;
	// 		for(int j = 0; j < C * 2; j++) if(0 <= j + delta * i && j + delta * i < C * 2) {
	// 			cmax(ndp[j + delta * i], dp[j] + delta);
	// 		}
	// 	}
	// 	swap(dp, ndp);
	// }
	// ans += dp[l - tot + C];
	// if(ans < 0) cout << "impossible\n";
	// else cout << ans << '\n';

	int lim = mxM * mxM;
    vector<int> f(2 * lim + 1, -1e9);
    f[lim] = 0;
    for (int i = 1; i <= m; i++) {
        vector<int> g(2 * lim + 1, -1e9);
        for (int j = -lim; j <= lim; j++) if (f[lim + j] > -1e8) {
            for (int k = 0; k <= a[i + m] - b[i + m] && j + i * k <= lim; k++) {
                g[lim + j + i * k] = max(g[lim + j + i * k], f[lim + j] + k);
            }
            for (int k = 0; k <= b[i + m] && j - i * k >= -lim; k++) {
                g[lim + j - i * k] = max(g[lim + j - i * k], f[lim + j] - k);
            }
        }
        swap(f, g);
    }
    if (f[l - tot + lim] < -1e8) cout << "impossible\n";
    else cout << ans + f[l - tot + lim] << "\n";

}

• Subtask 1: 0 / 5
• Subtask 2: 0 / 15
• Subtask 3-1: 0 / 10
• Subtask 3-2: 0 / 10
• Subtask 4-1: 0 / 10
• Subtask 4-2: 0 / 10
• Subtask 5-1: 0 / 10
• Subtask 5-2: 0 / 10
• Subtask 6-1: 0 / 10
• Subtask 6-2: 0 / 10