oj.uz

Submission #96792

# Submission time Handle Problem Language Result Execution time Memory
96792 2019-02-12T03:04:46 Z qkxwsm Kangaroo (CEOI16_kangaroo) C++14
51 / 100
 2000 ms 77000 KB 
#pragma GCC optimize ("O3")
#pragma GCC target ("sse4")
#include <bits/stdc++.h>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/rope>

using namespace std;
using namespace __gnu_pbds;
using namespace __gnu_cxx;

random_device(rd);
mt19937 rng(rd());
const long long FIXED_RANDOM = chrono::steady_clock::now().time_since_epoch().count();

struct custom_hash
{
	template<class T>
	unsigned long long operator()(T v) const
	{
		unsigned long long x = v;
		x += FIXED_RANDOM;
		// x += 11400714819323198485ull;
		// x = (x ^ (x >> 30)) * 13787848793156543929ull;
		x = (x ^ (x >> 27)) * 10723151780598845931ull;
		return x ^ (x >> 31);
	}
};

template<class T> using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
template<class T, class U> using hash_table = gp_hash_table<T, U, custom_hash>;

template<class T>
T randomize(T mod)
{
	return (uniform_int_distribution<T>(0, mod - 1))(rng);
}
template<class T>
void readi(T &x)
{
	x = 0;
	bool negative = false;
	char c = ' ';
	while (c < '-')
	{
		c = getchar();
	}
	if (c == '-')
	{
		negative = true;
		c = getchar();
	}
	while (c >= '0')
	{
		x = x * 10 + (c - '0');
		c = getchar();
	}
	if (negative)
	{
		x = -x;
	}
}
template<class T>
void printi(T output)
{
	if (output == 0)
	{
		putchar('0');
		return;
	}
	if (output < 0)
	{
		putchar('-');
		output = -output;
	}
	int buf[20], n = 0;
	while(output)
	{
		buf[n] = ((output % 10));
		output /= 10;
		n++;
	}
	for (n--; n >= 0; n--)
	{
		putchar(buf[n] + '0');
	}
	return;
}
template<class T>
void ckmin(T &a, T b)
{
	a = min(a, b);
}
template<class T>
void ckmax(T &a, T b)
{
	a = max(a, b);
}
long long expo(long long a, long long e, long long mod)
{
	return ((e == 0) ? 1 : ((expo(a * a % mod, e >> 1, mod)) * ((e & 1) ? a : 1) % mod));
}
template<class T, class U>
void nmod(T &x, U mod)
{
	if (x >= mod) x -= mod;
}
template<class T>
T gcd(T a, T b)
{
	return (b ? gcd(b, a % b) : a);
}

#define y0 ___y0
#define y1 ___y1
#define MP make_pair
#define PB push_back
#define LB lower_bound
#define UB upper_bound
#define fi first
#define se second
#define DBG(x) cerr << #x << " = " << (x) << endl
#define SZ(x) ((int) ((x).size()))
#define FOR(i, a, b) for (auto i = (a); i < (b); i++)
#define FORD(i, a, b) for (auto i = (a) - 1; i >= (b); i--)
#define ALL(x) (x).begin(), (x).end()

const long double PI = 4.0 * atan(1.0);
const long double EPS = 1e-9;

#define MAGIC 347
#define SINF 10007
#define CO 1000007
#define INF 1000000007
#define BIG 1000000931
#define LARGE 1696969696967ll
#define GIANT 2564008813937411ll
#define LLINF 2696969696969696969ll
#define MAXN 213

typedef long long ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef pair<ld, ld> pdd;
typedef vector<int> vi;
typedef vector<ll> vl;
typedef vector<ld> vd;
typedef vector<pii> vpi;
typedef vector<pll> vpl;
typedef vector<pdd> vpd;

int N, S, T;
ll dp[MAXN][2][MAXN][MAXN];
ll ans;

// ll solve(bool flag, int cur, int goal, int tot)
// {
// 	if (cur == goal)
// 	{
// 		if (tot == 1) return 1ll;
// 		return 0ll;
// 	}
// 	if (tot == 1)
// 	{
// 		return 0ll;
// 	}
// 	if (vis[flag][cur][goal][tot])
// 	{
// 		return dp[flag][cur][goal][tot];
// 	}
// 	vis[flag][cur][goal][tot] = true;
// 	// cerr << flag << ' ' << cur << ' ' << goal << ' ' << tot << endl;
// 	ll res = 0;
// 	if (flag == 1)
// 	{
// 		FOR(i, cur + 1, tot)
// 		{
// 			res += solve(0, i - 1, goal - (bool) (cur <= goal), tot - 1);
// 			nmod(res, INF);
// 		}
// 	}
// 	if (flag == 0)
// 	{
// 		FOR(i, 0, cur)
// 		{
// 			res += solve(1, i, goal - (bool) (cur <= goal), tot - 1);
// 			nmod(res, INF);
// 		}
// 	}
// 	dp[flag][cur][goal][tot] = res;
// 	// cerr << flag << ' '<< cur << ' ' << goal << ' ' << tot << ' ' << res << endl;
// 	return res;
// 	//# of guys to the left of me, # of guys to the right of me
// 	//i am going right!
// }

int32_t main()
{
	ios_base::sync_with_stdio(0); cin.tie(0);
	// cout << fixed << setprecision(10);
	// cerr << fixed << setprecision(10);
	// if (fopen("file.in", "r"))
	// {
	// 	freopen ("file.in", "r", stdin);
	// 	freopen ("file.out", "w", stdout);
	// }
	cin >> N >> S >> T;
	S--; T--;
	dp[1][0][0][0] = dp[1][1][0][0] = 1;
	FOR(tot, 2, N + 1)
	{
		FOR(flag, 0, 2)
		{
			FOR(cur, 0, tot)
			{
				FOR(goal, 0, tot)
				{
					if (cur == goal) continue;
					if (flag == 1)
					{
						FOR(i, cur + 1, tot)
						{
							dp[tot][flag][goal][cur] += dp[tot - 1][0][goal - (bool) (cur <= goal)][i - 1];
							nmod(dp[tot][flag][goal][cur], INF);
						}
					}
					if (flag == 0)
					{
						FOR(i, 0, cur)
						{
							dp[tot][flag][goal][cur] += dp[tot - 1][1][goal - (bool) (cur <= goal)][i];
							nmod(dp[tot][flag][goal][cur], INF);
						}
					}
				}
			}
		}
	}
	ans = dp[N][0][T][S] + dp[N][1][T][S];
	// ans = solve(0, S, T, N) + solve(1, S, T, N);
	nmod(ans, INF);
	cout << ans << '\n';
	//your state can be described by:
	//where you are! where the end is! how many there are! direction!
	// cerr << "time elapsed = " << (clock() / (CLOCKS_PER_SEC / 1000)) << " ms" << endl;
	return 0;
}
/* READ READ READ
* int overflow, maxn too small, special cases (n=1?, two distinct?), cin.tie() interactive
* reread the problem, try small cases
* note down possible sources of error as you go
* do smth instead of nothing
*/

Subtask #1
6.0 / 6.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 376 KB Output is correct
2 Correct 2 ms 504 KB Output is correct

Subtask #2
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 376 KB Output is correct
2 Correct 2 ms 504 KB Output is correct
3 Correct 3 ms 1656 KB Output is correct
4 Correct 7 ms 3320 KB Output is correct
5 Correct 7 ms 3192 KB Output is correct
6 Correct 7 ms 3320 KB Output is correct
7 Correct 6 ms 2940 KB Output is correct
8 Correct 7 ms 3192 KB Output is correct
9 Correct 7 ms 3320 KB Output is correct
10 Correct 9 ms 3320 KB Output is correct
11 Correct 7 ms 3192 KB Output is correct

Subtask #3
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 376 KB Output is correct
2 Correct 2 ms 504 KB Output is correct
3 Correct 3 ms 1656 KB Output is correct
4 Correct 7 ms 3320 KB Output is correct
5 Correct 7 ms 3192 KB Output is correct
6 Correct 7 ms 3320 KB Output is correct
7 Correct 6 ms 2940 KB Output is correct
8 Correct 7 ms 3192 KB Output is correct
9 Correct 7 ms 3320 KB Output is correct
10 Correct 9 ms 3320 KB Output is correct
11 Correct 7 ms 3192 KB Output is correct
12 Correct 1647 ms 68264 KB Output is correct
13 Correct 1279 ms 60536 KB Output is correct
14 Correct 1701 ms 68088 KB Output is correct
15 Correct 1667 ms 68984 KB Output is correct
16 Correct 1659 ms 68344 KB Output is correct
17 Correct 1694 ms 68908 KB Output is correct
18 Correct 1083 ms 54928 KB Output is correct
19 Correct 1591 ms 66780 KB Output is correct
20 Correct 1661 ms 68856 KB Output is correct

Subtask #4
0 / 49.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 376 KB Output is correct
2 Correct 2 ms 504 KB Output is correct
3 Correct 3 ms 1656 KB Output is correct
4 Correct 7 ms 3320 KB Output is correct
5 Correct 7 ms 3192 KB Output is correct
6 Correct 7 ms 3320 KB Output is correct
7 Correct 6 ms 2940 KB Output is correct
8 Correct 7 ms 3192 KB Output is correct
9 Correct 7 ms 3320 KB Output is correct
10 Correct 9 ms 3320 KB Output is correct
11 Correct 7 ms 3192 KB Output is correct
12 Correct 1647 ms 68264 KB Output is correct
13 Correct 1279 ms 60536 KB Output is correct
14 Correct 1701 ms 68088 KB Output is correct
15 Correct 1667 ms 68984 KB Output is correct
16 Correct 1659 ms 68344 KB Output is correct
17 Correct 1694 ms 68908 KB Output is correct
18 Correct 1083 ms 54928 KB Output is correct
19 Correct 1591 ms 66780 KB Output is correct
20 Correct 1661 ms 68856 KB Output is correct
21 Execution timed out 2078 ms 77000 KB Time limit exceeded
22 Halted 0 ms 0 KB -