# |
Submission time |
Handle |
Problem |
Language |
Result |
Execution time |
Memory |
464563 |
2021-08-13T12:42:22 Z |
SamAnd |
Exam (eJOI20_exam) |
C++17 |
|
0 ms |
0 KB |
#include <bits/stdc++.h>
using namespace std;
#define m_p make_pair
#define all(x) (x).begin(),(x).end()
#define sz(x) ((int)(x).size())
#define fi first
#define se second
typedef long long ll;
mt19937 rnd(chrono::steady_clock::now().time_since_epoch().count());
mt19937 rnf(2106);
const int N = 100005, N0 = 5003;
int n;
int a[N], b[N];
int maxi[N0][N0];
vector<int> v[N];
void rec0(int l, int r, int p)
{
if (l > r)
return;
int m = maxi[l][r];
rec0(l, m - 1, m);
rec0(m + 1, r, m);
if (p == 0)
return;
else if (p == l - 1)
{
for (int i = l; i <= r; ++i)
{
if (b[i] == a[p])
v[m].push_back(i);
}
}
else if (p == r + 1)
{
for (int i = r; i >= l; --i)
{
if (b[i] == a[p])
v[m].push_back(i);
}
reverse(all(v[m]));
}
else
assert(false);
}
int dp[N0 * N0];
int rec(int l, int r, int ul, int ur, int p)
{
if (l > r)
return 0;
ul = max(ul, l - 1);
ur = min(ur, r + 1);
if (ul + 1 >= ur)
return 0;
int m = maxi[l][r];
ll h = ul * 1LL * N0 * N0 + m * 1LL * N0 + ur;
if (dp.find(h) != dp.end())
return dp[h];
if (ul < m && m < ur && a[m] == b[m])
dp[h] = rec(l, m - 1, ul, ur, m) + rec(m + 1, r, ul, ur, m) + 1;
else
dp[h] = rec(l, m - 1, ul, ur, m) + rec(m + 1, r, ul, ur, m);
if (p == 0)
{
return dp[h];
}
if (p == l - 1)
{
int q = 0;
//for (int i = ul + 1; i <= ur - 1; ++i)
int s = upper_bound(all(v[m]), ul) - v[m].begin();
for (int ii = s; ii < sz(v[m]); ++ii)
{
int i = v[m][ii];
if (!(ul < i && i < ur))
break;
bool z = false;
if (b[i] == a[p])
{
z = true;
++q;
}
if (i < m && m < ur && a[m] == b[m])
++q;
if (z)
dp[h] = max(dp[h], q + rec(l, m - 1, i, ur, m) + rec(m + 1, r, i, ur, m));
if (i < m && m < ur && a[m] == b[m])
--q;
}
}
else if (p == r + 1)
{
int q = 0;
//for (int i = ur - 1; i >= ul + 1; --i)
int s = lower_bound(all(v[m]), ur) - v[m].begin();
for (int ii = s - 1; ii >= 0; --ii)
{
int i = v[m][ii];
if (!(ul < i && i < ur))
continue;
bool z = false;
if (b[i] == a[p])
{
z = true;
++q;
}
if (ul < m && m < i && a[m] == b[m])
++q;
dp[h] = max(dp[h], q + rec(l, m - 1, ul, i, m) + rec(m + 1, r, ul, i, m));
if (ul < m && m < i && a[m] == b[m])
--q;
}
}
else
assert(false);
return dp[h];
}
int solv0()
{
for (int l = 1; l <= n; ++l)
{
maxi[l][l] = l;
for (int r = l + 1; r <= n; ++r)
{
maxi[l][r] = maxi[l][r - 1];
if (a[r] > a[maxi[l][r]])
maxi[l][r] = r;
}
}
for (int i = 1; i <= n; ++i)
v[i].clear();
rec0(1, n, 0);
dp.clear();
return rec(1, n, 0, n + 1, 0);
}
int p[N];
int ul[N], ur[N];
int solv2()
{
for (int i = 1; i <= n; ++i)
{
p[i] = p[i - 1];
if (a[i] == b[i])
++p[i];
}
ul[0] = 0;
for (int i = 1; i <= n; ++i)
{
if (a[i] > b[i])
{
ul[i] = i;
}
else
{
ul[i] = ul[i - 1];
}
}
ur[n + 1] = n + 1;
for (int i = n; i >= 1; --i)
{
if (a[i] > b[i])
{
ur[i] = i;
}
else
{
ur[i] = ur[i + 1];
}
}
int ans = 0;
for (int i = 1; i <= n; ++i)
{
if (a[i] <= b[i])
{
if (p[ur[i] - 1] - p[ul[i]] > 0)
++ans;
}
}
return ans;
}
void solv()
{
cin >> n;
for (int i = 1; i <= n; ++i)
cin >> a[i];
for (int i = 1; i <= n; ++i)
cin >> b[i];
if (n <= 5000)
{
cout << solv0() << "\n";
return;
}
bool z2 = true;
for (int i = 1; i <= n; ++i)
{
if (b[i] != b[1])
{
z2 = false;
break;
}
}
if (z2)
{
cout << solv2() << "\n";
return;
}
}
int main()
{
#ifdef SOMETHING
freopen("input.txt", "r", stdin);
//freopen("output.txt", "w", stdout);
#endif // SOMETHING
ios_base::sync_with_stdio(false), cin.tie(0);
/*int st = 100;
while (st--)
{
n = rnf() % 100 + 1;
for (int i = 1; i <= n; ++i)
{
a[i] = rnf() % 100 + 1;
}
b[1] = a[rnf() % n + 1];
for (int i = 2; i <= n; ++i)
b[i] = b[1];
if (solv0() != solv2())
{
cout << "WA\n";
return 0;
}
}
cout << "OK\n";
return 0;*/
int tt = 1;
//cin >> tt;
while (tt--)
{
solv();
}
return 0;
}
Compilation message
exam.cpp: In function 'int rec(int, int, int, int, int)':
exam.cpp:65:12: error: request for member 'find' in 'dp', which is of non-class type 'int [25030009]'
65 | if (dp.find(h) != dp.end())
| ^~~~
exam.cpp:65:26: error: request for member 'end' in 'dp', which is of non-class type 'int [25030009]'
65 | if (dp.find(h) != dp.end())
| ^~~
exam.cpp: In function 'int solv0()':
exam.cpp:152:8: error: request for member 'clear' in 'dp', which is of non-class type 'int [25030009]'
152 | dp.clear();
| ^~~~~