Submission #109250

# Submission time Handle Problem Language Result Execution time Memory
109250 2019-05-05T23:56:23 Z qkxwsm Riddick's Cube (IZhO13_riddicks) C++14
100 / 100
23 ms 512 KB
//clever
#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 100500
#define BIG 1000000931
#define LARGE 1696969696967ll
#define GIANT 2564008813937411ll
#define LLINF 2696969696969696969ll
#define MAXN 5

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;
typedef vector<vector<int> > grid;

int N, M;
grid beg;
int ans = INF;

int dist(vi a, vi b)
{
	int res = INF;
	FOR(i, 1, SZ(b) + 1)
	{
		rotate(b.begin(), b.begin() + 1, b.end());
		if (a == b) ckmin(res, min(i, SZ(b) - i));
	}
	return res;
}
int finish(grid g)
{
	//each row must be a cyclic shift of the first row!
	int res = INF;
	bool flag = false;
	FOR(i, 0, N)
	{
		FOR(j, 0, M)
		{
			if (g[i][j] != g[i][0]) flag = true;
		}
	}
	if (!flag) return 0;
	FOR(i, 1, M + 1)
	{
		int cur = min(i, M - i);
		rotate(g[0].begin(), g[0].begin() + 1, g[0].end());
		FOR(j, 1, N)
		{
			cur += dist(g[j], g[0]);
		}
		ckmin(res, cur);
	}
	return res;
}
void test(int idx, int cost)
{
	//shift column #idx!
	if (idx == M)
	{
		ckmin(ans, cost + finish(beg));
		return;
	}
	//shift the idxth column
	FOR(i, 1, N + 1)
	{
		int x = beg[0][idx];
		FOR(j, 0, N - 1)
		{
			beg[j][idx] = beg[j + 1][idx];
		}
		beg[N - 1][idx] = x;
		test(idx + 1, cost + min(i, N - i));
	}
}

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 >> M;
	beg.resize(N); FOR(i, 0, N) beg[i].resize(M);
	FOR(i, 0, N)
	{
		FOR(j, 0, M)
		{
			cin >> beg[i][j];
		}
	}
	test(0, 0);
	cout << ans << '\n';
	// 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
*/
# Verdict Execution time Memory Grader output
1 Correct 2 ms 384 KB Output is correct
2 Correct 2 ms 384 KB Output is correct
3 Correct 2 ms 384 KB Output is correct
4 Correct 2 ms 384 KB Output is correct
5 Correct 2 ms 384 KB Output is correct
6 Correct 2 ms 384 KB Output is correct
7 Correct 2 ms 384 KB Output is correct
8 Correct 2 ms 384 KB Output is correct
9 Correct 6 ms 384 KB Output is correct
10 Correct 4 ms 384 KB Output is correct
11 Correct 8 ms 512 KB Output is correct
12 Correct 4 ms 384 KB Output is correct
13 Correct 13 ms 384 KB Output is correct
14 Correct 23 ms 384 KB Output is correct
15 Correct 17 ms 384 KB Output is correct
16 Correct 13 ms 384 KB Output is correct
17 Correct 14 ms 384 KB Output is correct
18 Correct 13 ms 384 KB Output is correct
19 Correct 17 ms 428 KB Output is correct
20 Correct 13 ms 384 KB Output is correct