Submission #102252

# Submission time Handle Problem Language Result Execution time Memory
102252 2019-03-23T23:56:05 Z qkxwsm Lamps (JOI19_lamps) C++14
100 / 100
69 ms 34740 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 1000013

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;
int s[MAXN], t[MAXN];
int dp[MAXN][3][2];
int c1[2][2], c2[3][3];
int ans = INF;

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;
	string temps; cin >> temps;
	FOR(i, 0, N)
	{
		s[i] = (temps[i] == '1');
	}
	cin >> temps;
	FOR(i, 0, N)
	{
		t[i] = (temps[i] == '1');
	}
	//all the number changing goes at the start
	c1[0][0] = 0; c1[0][1] = 1;
	c1[1][0] = 0; c1[1][1] = 0;
	c2[0][0] = 0; c2[0][1] = 1; c2[0][2] = 0;
	c2[1][0] = 1; c2[1][1] = 0; c2[1][2] = 0;
	c2[2][0] = 1; c2[2][1] = 1; c2[2][2] = 0;
	FOR(i, 0, N + 1)
	{
		FOR(j, 0, 3)
		{
			FOR(k, 0, 2)
			{
				dp[i][j][k] = INF;
			}
		}
	}
	dp[0][2][0] = 0;
	FOR(i, 0, N)
	{
		FOR(j, 0, 3)
		{
			FOR(k, 0, 2)
			{
				//first we changed it to j, then we toggled if k
				FOR(m, 0, 3)
				{
					FOR(n, 0, 2)
					{
						int num = s[i];
						if (m != 2) num = m;
						if (n) num ^= 1;
						if (num != t[i]) continue;
						ckmin(dp[i + 1][m][n], dp[i][j][k] + c2[j][m] + c1[k][n]);
					}
				}
			}
		}
	}
	FOR(i, 0, 3)
	{
		FOR(j, 0, 2)
		{
			ckmin(ans, dp[N][i][j]);
		}
	}
	cout << ans << '\n';
	//dp[position][active or not?] = minimum umber of changes
	//all toggles come after 0's and 1's!
	//dp[position][# of toggles][active?] = # of single changes needed?
	// 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 3 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 2 ms 384 KB Output is correct
10 Correct 2 ms 384 KB Output is correct
11 Correct 2 ms 356 KB Output is correct
12 Correct 3 ms 384 KB Output is correct
13 Correct 2 ms 384 KB Output is correct
14 Correct 2 ms 384 KB Output is correct
15 Correct 2 ms 384 KB Output is correct
16 Correct 2 ms 384 KB Output is correct
17 Correct 2 ms 384 KB Output is correct
18 Correct 2 ms 384 KB Output is correct
19 Correct 2 ms 384 KB Output is correct
20 Correct 3 ms 384 KB Output is correct
21 Correct 2 ms 384 KB Output is correct
22 Correct 2 ms 384 KB Output is correct
23 Correct 2 ms 384 KB Output is correct
24 Correct 3 ms 384 KB Output is correct
25 Correct 2 ms 384 KB Output is correct
26 Correct 2 ms 384 KB Output is correct
27 Correct 2 ms 384 KB Output is correct
28 Correct 3 ms 384 KB Output is correct
29 Correct 2 ms 384 KB Output is correct
30 Correct 2 ms 384 KB Output is correct
31 Correct 2 ms 384 KB Output is correct
32 Correct 2 ms 384 KB Output is correct
33 Correct 2 ms 512 KB Output is correct
34 Correct 3 ms 384 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 2 ms 384 KB Output is correct
2 Correct 3 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 2 ms 384 KB Output is correct
10 Correct 2 ms 384 KB Output is correct
11 Correct 2 ms 356 KB Output is correct
12 Correct 3 ms 384 KB Output is correct
13 Correct 2 ms 384 KB Output is correct
14 Correct 2 ms 384 KB Output is correct
15 Correct 2 ms 384 KB Output is correct
16 Correct 2 ms 384 KB Output is correct
17 Correct 2 ms 384 KB Output is correct
18 Correct 2 ms 384 KB Output is correct
19 Correct 2 ms 384 KB Output is correct
20 Correct 3 ms 384 KB Output is correct
21 Correct 2 ms 384 KB Output is correct
22 Correct 2 ms 384 KB Output is correct
23 Correct 2 ms 384 KB Output is correct
24 Correct 3 ms 384 KB Output is correct
25 Correct 2 ms 384 KB Output is correct
26 Correct 2 ms 384 KB Output is correct
27 Correct 2 ms 384 KB Output is correct
28 Correct 3 ms 384 KB Output is correct
29 Correct 2 ms 384 KB Output is correct
30 Correct 2 ms 384 KB Output is correct
31 Correct 2 ms 384 KB Output is correct
32 Correct 2 ms 384 KB Output is correct
33 Correct 2 ms 512 KB Output is correct
34 Correct 3 ms 384 KB Output is correct
35 Correct 2 ms 512 KB Output is correct
36 Correct 3 ms 512 KB Output is correct
37 Correct 3 ms 512 KB Output is correct
38 Correct 2 ms 384 KB Output is correct
39 Correct 2 ms 384 KB Output is correct
40 Correct 3 ms 512 KB Output is correct
41 Correct 2 ms 512 KB Output is correct
42 Correct 3 ms 512 KB Output is correct
43 Correct 3 ms 512 KB Output is correct
44 Correct 3 ms 512 KB Output is correct
45 Correct 2 ms 512 KB Output is correct
46 Correct 2 ms 384 KB Output is correct
47 Correct 2 ms 512 KB Output is correct
48 Correct 3 ms 512 KB Output is correct
49 Correct 2 ms 384 KB Output is correct
50 Correct 3 ms 384 KB Output is correct
51 Correct 3 ms 512 KB Output is correct
52 Correct 2 ms 384 KB Output is correct
53 Correct 3 ms 512 KB Output is correct
54 Correct 2 ms 384 KB Output is correct
55 Correct 3 ms 512 KB Output is correct
56 Correct 2 ms 384 KB Output is correct
57 Correct 3 ms 512 KB Output is correct
58 Correct 3 ms 512 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 3 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 3 ms 384 KB Output is correct
6 Correct 2 ms 384 KB Output is correct
7 Correct 57 ms 34704 KB Output is correct
8 Correct 54 ms 34708 KB Output is correct
9 Correct 48 ms 34708 KB Output is correct
10 Correct 53 ms 34708 KB Output is correct
11 Correct 51 ms 34708 KB Output is correct
12 Correct 58 ms 34708 KB Output is correct
13 Correct 53 ms 34708 KB Output is correct
14 Correct 58 ms 34708 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 2 ms 384 KB Output is correct
2 Correct 3 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 2 ms 384 KB Output is correct
10 Correct 2 ms 384 KB Output is correct
11 Correct 2 ms 356 KB Output is correct
12 Correct 3 ms 384 KB Output is correct
13 Correct 2 ms 384 KB Output is correct
14 Correct 2 ms 384 KB Output is correct
15 Correct 2 ms 384 KB Output is correct
16 Correct 2 ms 384 KB Output is correct
17 Correct 2 ms 384 KB Output is correct
18 Correct 2 ms 384 KB Output is correct
19 Correct 2 ms 384 KB Output is correct
20 Correct 3 ms 384 KB Output is correct
21 Correct 2 ms 384 KB Output is correct
22 Correct 2 ms 384 KB Output is correct
23 Correct 2 ms 384 KB Output is correct
24 Correct 3 ms 384 KB Output is correct
25 Correct 2 ms 384 KB Output is correct
26 Correct 2 ms 384 KB Output is correct
27 Correct 2 ms 384 KB Output is correct
28 Correct 3 ms 384 KB Output is correct
29 Correct 2 ms 384 KB Output is correct
30 Correct 2 ms 384 KB Output is correct
31 Correct 2 ms 384 KB Output is correct
32 Correct 2 ms 384 KB Output is correct
33 Correct 2 ms 512 KB Output is correct
34 Correct 3 ms 384 KB Output is correct
35 Correct 2 ms 512 KB Output is correct
36 Correct 3 ms 512 KB Output is correct
37 Correct 3 ms 512 KB Output is correct
38 Correct 2 ms 384 KB Output is correct
39 Correct 2 ms 384 KB Output is correct
40 Correct 3 ms 512 KB Output is correct
41 Correct 2 ms 512 KB Output is correct
42 Correct 3 ms 512 KB Output is correct
43 Correct 3 ms 512 KB Output is correct
44 Correct 3 ms 512 KB Output is correct
45 Correct 2 ms 512 KB Output is correct
46 Correct 2 ms 384 KB Output is correct
47 Correct 2 ms 512 KB Output is correct
48 Correct 3 ms 512 KB Output is correct
49 Correct 2 ms 384 KB Output is correct
50 Correct 3 ms 384 KB Output is correct
51 Correct 3 ms 512 KB Output is correct
52 Correct 2 ms 384 KB Output is correct
53 Correct 3 ms 512 KB Output is correct
54 Correct 2 ms 384 KB Output is correct
55 Correct 3 ms 512 KB Output is correct
56 Correct 2 ms 384 KB Output is correct
57 Correct 3 ms 512 KB Output is correct
58 Correct 3 ms 512 KB Output is correct
59 Correct 3 ms 384 KB Output is correct
60 Correct 2 ms 384 KB Output is correct
61 Correct 2 ms 384 KB Output is correct
62 Correct 2 ms 384 KB Output is correct
63 Correct 3 ms 384 KB Output is correct
64 Correct 2 ms 384 KB Output is correct
65 Correct 57 ms 34704 KB Output is correct
66 Correct 54 ms 34708 KB Output is correct
67 Correct 48 ms 34708 KB Output is correct
68 Correct 53 ms 34708 KB Output is correct
69 Correct 51 ms 34708 KB Output is correct
70 Correct 58 ms 34708 KB Output is correct
71 Correct 53 ms 34708 KB Output is correct
72 Correct 58 ms 34708 KB Output is correct
73 Correct 56 ms 34660 KB Output is correct
74 Correct 54 ms 34740 KB Output is correct
75 Correct 46 ms 34576 KB Output is correct
76 Correct 49 ms 34676 KB Output is correct
77 Correct 48 ms 34708 KB Output is correct
78 Correct 46 ms 34588 KB Output is correct
79 Correct 49 ms 34712 KB Output is correct
80 Correct 50 ms 34580 KB Output is correct
81 Correct 52 ms 34580 KB Output is correct
82 Correct 51 ms 34708 KB Output is correct
83 Correct 58 ms 34708 KB Output is correct
84 Correct 57 ms 34708 KB Output is correct
85 Correct 58 ms 34580 KB Output is correct
86 Correct 56 ms 34580 KB Output is correct
87 Correct 59 ms 34584 KB Output is correct
88 Correct 61 ms 34576 KB Output is correct
89 Correct 57 ms 34676 KB Output is correct
90 Correct 52 ms 34576 KB Output is correct
91 Correct 53 ms 34708 KB Output is correct
92 Correct 69 ms 34708 KB Output is correct
93 Correct 56 ms 34576 KB Output is correct
94 Correct 54 ms 34708 KB Output is correct
95 Correct 58 ms 34676 KB Output is correct
96 Correct 54 ms 34708 KB Output is correct
97 Correct 55 ms 34716 KB Output is correct
98 Correct 53 ms 34716 KB Output is correct
99 Correct 69 ms 34708 KB Output is correct
100 Correct 58 ms 34576 KB Output is correct
101 Correct 54 ms 34580 KB Output is correct
102 Correct 56 ms 34708 KB Output is correct