#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;
template<typename T> using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
typedef long long int ll;
typedef long double ld;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
#define fastio ios_base::sync_with_stdio(false); cin.tie(NULL)
#define pb push_back
#define endl '\n'
#define sz(a) (int)a.size()
#define setbits(x) __builtin_popcountll(x)
#define ff first
#define ss second
#define conts continue
#define ceil2(x,y) ((x+y-1)/(y))
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define yes cout << "Yes" << endl
#define no cout << "No" << endl
#define rep(i,n) for(int i = 0; i < n; ++i)
#define rep1(i,n) for(int i = 1; i <= n; ++i)
#define rev(i,s,e) for(int i = s; i >= e; --i)
#define trav(i,a) for(auto &i : a)
template<typename T>
void amin(T &a, T b) {
a = min(a,b);
}
template<typename T>
void amax(T &a, T b) {
a = max(a,b);
}
#ifdef LOCAL
#include "debug.h"
#else
#define debug(...) 42
#endif
/*
read some solutions a long time ago, remember some key ideas from there
*/
const int MOD = 1e9 + 7;
const int N = 1e5 + 5;
const int inf1 = int(1e9) + 5;
const ll inf2 = ll(1e18) + 5;
#include "communication.h"
//
// --- Sample implementation for the task communication ---
//
// To compile this program with the sample grader, place:
// communication.h communication_sample.cpp sample_grader.cpp
// in a single folder, then open the terminal in this directory (right-click onto an empty spot in the directory,
// left click on "Open in terminal") and enter e.g.:
// g++ -std=c++17 communication_sample.cpp sample_grader.cpp
// in this folder. This will create a file a.out in the current directory which you can execute from the terminal
// as ./a.out
// See task statement or sample_grader.cpp for the input specification
//
void encode(int n, int k) {
int currn = 1;
while(currn <= n){
currn <<= 1;
}
n = currn;
mt19937 rng(n);
int xo = rng()%n;
k--;
k ^= xo;
k++;
vector<int> a = {0,6,9,15};
vector<vector<int>> possible(4);
rep(i,4){
int x = a[i];
rep(mask,1<<4){
int pb = -1;
bool ok = true;
rep(bit,4){
int b = 0;
if(mask&(1<<bit)) b = 1;
if(b == 1 and pb == 1){
ok = false;
}
pb = b;
}
if(ok){
possible[i].pb(x^mask);
}
}
}
map<int,int> mp;
mp[1] = 0, mp[n+1] = 0;
auto range_add = [&](int l, int r, int x){
mp[l] += x, mp[r+1] -= x;
};
auto cnt_zero = [&](){
vector<pii> b(all(mp));
int sum = 0;
int cnt = 0;
rep(i,sz(b)-1){
sum += b[i].ss;
if(sum == 0){
int len = b[i+1].ff-b[i].ff;
cnt += len;
}
}
return cnt;
};
auto kth_zero = [&](int k){
vector<pii> b(all(mp));
int sum = 0;
rep(i,sz(b)-1){
sum += b[i].ss;
if(sum == 0){
int len = b[i+1].ff-b[i].ff;
if(k <= len){
return b[i].ff+k-1;
}
else{
k -= len;
}
}
}
assert(0);
return -1;
};
auto my_send = [&](int i){
int x = a[i], y = 0;
rep(bit,4){
int b = 0;
if(x&(1<<bit)) b = 1;
int sent = send(b);
y |= sent*(1<<bit);
}
return y;
};
while(true){
int active = cnt_zero();
if(active <= 2) break;
vector<int> lens;
int s1 = active/4, c1 = 4;
int s2 = ceil2(active,4), c2 = active%4;
c1 -= c2;
rep(i,c1) lens.pb(s1);
rep(i,c2) lens.pb(s2);
vector<pii> ranges;
int z = 0;
rep(i,4){
int len = lens[i];
if(!len){
ranges.pb({0,0});
}
else{
int l = kth_zero(z+1), r = kth_zero(z+len);
z += len;
ranges.pb({l,r});
}
}
int to_send = -1;
rep(i,4){
auto [l,r] = ranges[i];
if(l <= k and r >= k){
to_send = i;
}
}
int x = my_send(to_send);
vector<int> bad;
rep(i,4){
if(!count(all(possible[i]),x)){
bad.pb(i);
}
}
trav(i,bad){
if(ranges[i].ff == -1) conts;
range_add(ranges[i].ff,ranges[i].ss,1);
}
}
}
std::pair<int, int> decode(int n) {
int currn = 1;
while(currn <= n){
currn <<= 1;
}
int on = n;
n = currn;
mt19937 rng(n);
int xo = rng()%n;
vector<int> a = {0,6,9,15};
vector<vector<int>> possible(4);
rep(i,4){
int x = a[i];
rep(mask,1<<4){
int pb = -1;
bool ok = true;
rep(bit,4){
int b = 0;
if(mask&(1<<bit)) b = 1;
if(b == 1 and pb == 1){
ok = false;
}
pb = b;
}
if(ok){
possible[i].pb(x^mask);
}
}
}
map<int,int> mp;
mp[1] = 0, mp[n+1] = 0;
auto range_add = [&](int l, int r, int x){
mp[l] += x, mp[r+1] -= x;
};
auto cnt_zero = [&](){
vector<pii> b(all(mp));
int sum = 0;
int cnt = 0;
rep(i,sz(b)-1){
sum += b[i].ss;
if(sum == 0){
int len = b[i+1].ff-b[i].ff;
cnt += len;
}
}
return cnt;
};
auto kth_zero = [&](int k){
vector<pii> b(all(mp));
int sum = 0;
rep(i,sz(b)-1){
sum += b[i].ss;
if(sum == 0){
int len = b[i+1].ff-b[i].ff;
if(k <= len){
return b[i].ff+k-1;
}
else{
k -= len;
}
}
}
assert(0);
return -1;
};
auto my_receive = [&](){
int x = 0;
rep(bit,4){
x = x<<1|receive();
}
return x;
};
while(true){
int active = cnt_zero();
if(active <= 2) break;
vector<int> lens;
int s1 = active/4, c1 = 4;
int s2 = ceil2(active,4), c2 = active%4;
c1 -= c2;
rep(i,c1) lens.pb(s1);
rep(i,c2) lens.pb(s2);
vector<pii> ranges;
int z = 0;
rep(i,4){
int len = lens[i];
if(!len){
ranges.pb({0,0});
}
else{
int l = kth_zero(z+1), r = kth_zero(z+len);
z += len;
ranges.pb({l,r});
}
}
int x = my_receive();
vector<int> bad;
rep(i,4){
if(!count(all(possible[i]),x)){
bad.pb(i);
}
}
trav(i,bad){
if(ranges[i].ff == -1) conts;
range_add(ranges[i].ff,ranges[i].ss,1);
}
}
int active = cnt_zero();
pii res = {0,0};
res.ff = kth_zero(1);
res.ss = res.ff;
if(active == 2){
res.ss = kth_zero(2);
}
res.ff--, res.ss--;
res.ff ^= xo, res.ss ^= xo;
res.ff++, res.ss++;
if(res.ff > on) res.ff = 1;
if(res.ss > on) res.ss = 1;
cout << xo << endl;
cout << res.ff << " " << res.ss << endl;
return res;
}
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
2 ms |
420 KB |
Security violation! |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
336 ms |
428 KB |
Security violation! |
| 2 |
Halted |
0 ms |
0 KB |
- |
