#pragma GCC optimize ("O3")
#pragma GCC target("avx,avx2,fma")
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ld = long double;
int prob = 500;
#include "communication.h"
struct intervalset
{
int sz = 0;
vector<pair<int, int>>S;//sorted, disjoint
intervalset()
{
}
intervalset(int N)
{
sz = N;
S.push_back({1, N});
}
void append(pair<int, int> v)
{
sz += v.second - v.first + 1;
if (S.empty())
S.push_back(v);
else {
assert(v.first > S.back().second);
if (v.first == S.back().second + 1)
S.back().second = v.second;
else
S.push_back(v);
}
}
pair<intervalset, intervalset> split(int k)
{ //k,sz-k
intervalset A;
intervalset B;
for (pair<int, int>i : S)
{
if (i.second - i.first + 1 <= k)
{
A.append(i);
k -= i.second - i.first + 1;
}
else if (k <= 0)
{
B.append(i);
}
else
{
A.append({i.first, i.first + k - 1});
B.append({i.first + k, i.second});
k = 0;
}
}
return {A, B};
}
int kth(int k)
{
for (pair<int, int>i : S)
{
if (i.second - i.first + 1 < k)
{
k -= i.second - i.first + 1;
}
else
{
return i.first + (k - 1);
}
}
assert(false);
return 0;
}
int kelintas(int x)
{
int r = 0;
for (pair<int, int>i : S)
{
if (i.second < x)
r += (i.second - i.first + 1);
else if (x < i.first)
return 0;
else
return r + (x - i.first + 1);
}
return 0;
}
intervalset(const intervalset &A, const intervalset &B)
{
const vector<pair<int, int>>&a = A.S;
const vector<pair<int, int>>&b = B.S;
int i = 0;
int j = 0;
while (i < (int)a.size() && j < (int)b.size())
{
if (a[i].first < b[j].first)
append(a[i++]);
else
append(b[j++]);
}
while (i < (int)a.size())
append(a[i++]);
while (j < (int)b.size())
append(b[j++]);
}
};
int K[100][100];
pair<int, int> getbest(int A, int B)
{
assert(A + B < 100);
static bool prec = false;
if (prec == false)
{
prec = true;
for (int sum = 0; sum < 100; sum++)
{
if (sum <= 2)
{
for (int a = 0; a <= sum; a++) {
int b = sum - a;
K[a][b] = 0;
}
}
else {
for (int a = 0; a <= sum; a++)
{
int b = sum - a;
K[a][b] = 1000;
}
int rep = 1;
if (sum <= 4)
rep = 4;
for (int r = 0; r < rep; r++)
for (int a = 0; a <= sum; a++)
{
int b = sum - a;
for (int a0 = 0; a0 <= a; a0++)
{
for (int b0 = 0; b0 <= b; b0++)
{
int a_ = a0 + b0;
int b_ = b - b0;
int a__ = a - a0 + b - b0;
int b__ = a0;
K[a][b] = min(K[a][b], 1 + max(K[a_][b_], K[a__][b__]));
}
}
}
}
}
}
pair<int, pair<int, int>>best = {1000, {0, 0}};
for (int a0 = 0; a0 <= A; a0++)
{
for (int b0 = 0; b0 <= B; b0++)
{
int a_ = a0 + b0;
int b_ = B - b0;
int a__ = A - a0 + B - b0;
int b__ = a0;
best = min(best, {max(K[a_][b_], K[a__][b__]), {a0, b0}});
}
}
return best.second;
}
void encode(int N, int X)
{
intervalset A(N);
intervalset B;
mt19937 rng(0);
while (A.sz + B.sz > 2)
{
int a0 = A.sz / 2;
int b0 = B.sz / 2;
if (A.sz + B.sz < 100)
{
pair<int, int>c = getbest(A.sz, B.sz);
a0 = c.first;
b0 = c.second;
}
intervalset C(A, B);
int ka = A.kelintas(X);
int kb = B.kelintas(X);
int s = 1;
if (ka != 0 && ka <= a0)
s = 0;
if (kb != 0 && kb <= b0)
s = 0;
pair<intervalset, intervalset>A_ = A.split(a0);
pair<intervalset, intervalset>B_ = B.split(b0);
int r = send(s);
if (r == 0)
{
A = intervalset(A_.first, B_.first);
B = A_.second;
}
else
{
A = intervalset(A_.second, B_.second);
B = A_.first;
}
}
}
pair<int, int> decode(int N)
{
intervalset A(N);
intervalset B;
mt19937 rng(0);
while (A.sz + B.sz > 2)
{
int b0 = B.sz / 2;
int a0 = A.sz / 2;
if (A.sz + B.sz < 100)
{
pair<int, int>c = getbest(A.sz, B.sz);
a0 = c.first;
b0 = c.second;
}
pair<intervalset, intervalset>A_ = A.split(a0);
pair<intervalset, intervalset>B_ = B.split(b0);
int r = receive();
if (r == 0)
{
A = intervalset(A_.first, B_.first);
B = A_.second;
}
else
{
A = intervalset(A_.second, B_.second);
B = A_.first;
}
}
if (A.sz == 0)
return {B.S[0].first, B.S.back().second};
if (B.sz == 0)
return {A.S[0].first, A.S.back().second};
return {A.S[0].first, B.S[0].first};
}
// int main()
// {
// for (int test = 0; test < 20; test++)
// {
// int N = 1e9;
// int X = 3;
// encode(N, X);
// pair<int, int>a = decode(N);
// assert(a.first >= 1 && a.first <= N && a.second >= 1 && a.second <= N);
// assert(a.first == X || a.second == X);
// cout << kiekis << endl;
// kiekis = 0;
// }
// }
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
15 ms |
1896 KB |
Output is correct |
| 2 |
Correct |
15 ms |
1788 KB |
Output is correct |
| 3 |
Correct |
23 ms |
1836 KB |
Output is correct |
| 4 |
Correct |
15 ms |
1880 KB |
Output is correct |
| 5 |
Correct |
16 ms |
1804 KB |
Output is correct |
| 6 |
Correct |
43 ms |
2068 KB |
Output is correct |
| 7 |
Correct |
44 ms |
1876 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Partially correct |
898 ms |
1820 KB |
Output is partially correct |
| 2 |
Incorrect |
7 ms |
296 KB |
Not correct |
| 3 |
Halted |
0 ms |
0 KB |
- |
