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QOJ
ID | Problem | Submitter | Result | Time | Memory | Language | File size | Submit time | Judge time |
---|---|---|---|---|---|---|---|---|---|
#556293 | #9237. Message | zhangmj2008 | 0 | 226ms | 4100kb | C++17 | 3.2kb | 2024-09-10 16:38:40 | 2024-09-10 16:38:44 |
Judging History
answer
#include "message.h"
#include <bits/stdc++.h>
using namespace std;
using uint = unsigned int; using i64 = long long; using ui64 = unsigned long long; using i128 = __int128;
const int INF = 1e9; const i64 LLNF = 4e18;
template< class Tp > void chkmax( Tp &x, Tp y ) { x = max( x, y ); }
template< class Tp > void chkmin( Tp &x, Tp y ) { x = min( x, y ); }
int log( int x ) { return 31 - __builtin_clz( x ); }
int log( i64 x ) { return 63 - __builtin_clzll( x ); }
// 先把 <= 1024 长度通过补上 1000000, 变成 1025 长度的串. 现在只需要传输 1025 长度的串.
// 然后注意到有 66 * 16 - 1025 = 31 个可以另作他用的位置. 恰好是一次传输的长度.
// 所以设所有好的位置为 0 <= r[0] < ... <= r[15] <= 30. 则只需要传输 s[i] = ( r[i + 1] - r[i] ) % 31.
// 此时注意 sum s[i] = 31. 所以一样的, 在第 r[i] 个位置的前 s[i] 次传输中置为 000001. 总共使用了 31 个额外位置.
// 考虑 Bob 如何解密. 注意在第 u 列提取可以知道 u 的下一个好的位置 v. ( 在 u 是好位置的情况下 ).
// 所以现在连边 u -> v. 这就是一个 31 个点的基环树森林. 其中好的位置恰好构成一个长度为 16 的环. 这就很简单了.
void send_message( vector< bool > M, vector< bool > C ) {
int S = ( int ) M.size( );
M.emplace_back( 1 ); while( ( int ) M.size( ) < 1025 ) M.emplace_back( 0 );
vector< int > r;
for( int u = 0; u < 31; u ++ ) if( !C[u] ) r.emplace_back( u );
assert( ( int ) r.size( ) == 16 );
vector< int > s( 16 );
for( int i = 0; i < 16; i ++ ) s[i] = ( r[( i + 1 ) % 16] - r[i] + 31 ) % 31;
vector< vector< bool > > send( 66, vector< bool >( 31 ) ); vector< vector< bool > > used( 66, vector< bool >( 31 ) );
for( int i = 0; i < 16; i ++ )
for( int j = 0; j < s[i]; j ++ )
send[j][r[i]] = ( j == s[i] - 1 ) ? ( 1 ) : ( 0 ), used[j][r[i]] = true;
int cur = 0;
for( int k = 0; k < 66; k ++ )
for( int u = 0; u < 31; u ++ )
if( !C[u] && !used[k][u] )
send[k][u] = M[cur], used[k][u] = true, cur ++;
for( int k = 0; k < 66; k ++ )
send_packet( send[k] );
}
vector< bool > receive_message( vector< vector< bool > > R ) {
vector< int > nxt( 31 );
for( int u = 0; u < 31; u ++ ) {
int k = 0;
while( k < 66 && R[k][u] == 0 ) k ++;
nxt[u] = ( u + k + 1 ) % 31;
}
vector< bool > C( 31 );
for( int u = 0; u < 31; u ++ ) {
vector< bool > vis( 31, false ); int t = u;
while( !vis[t] ) vis[t] = true, t = nxt[t];
if( t == u && count( vis.begin( ), vis.begin( ) + 31, true ) == 16 ) {
for( int v = 0; v < 31; v ++ ) C[v] = !vis[v];
break;
}
}
vector< int > r;
for( int u = 0; u < 31; u ++ ) if( !C[u] ) r.emplace_back( u );
assert( ( int ) r.size( ) == 16 );
vector< int > s( 16 );
for( int i = 0; i < 16; i ++ ) s[i] = ( r[( i + 1 ) % 16] - r[i] + 31 ) % 31;
vector< vector< bool > > used( 66, vector< bool >( 31 ) );
for( int i = 0; i < 16; i ++ )
for( int j = 0; j < s[i]; j ++ )
used[j][i] = true;
vector< bool > M;
for( int k = 0; k < 66; k ++ )
for( int u = 0; u < 31; u ++ )
if( !C[u] && !used[k][u] )
M.emplace_back( R[k][u] ), used[k][u] = true;
while( !M.empty( ) && M.back( ) == 0 ) M.pop_back( ); M.pop_back( );
return M;
}
Details
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Subtask #1:
score: 0
Wrong Answer
Test #1:
score: 0
Wrong Answer
time: 153ms
memory: 3824kb
Manager to Aisha
Aisha to Manager
Manager to Basma
Basma to Manager
Manager to Checker
0 ing with message 'decoded message is incorrect' Sending secret with code DIE to mgr2sol[1] Quitting with result code 1
result:
wrong output format Extra information in the output file
Subtask #2:
score: 0
Wrong Answer
Test #8:
score: 0
Wrong Answer
time: 226ms
memory: 4100kb
Manager to Aisha
Aisha to Manager
Manager to Basma
Basma to Manager
Manager to Checker
0 ing with message 'decoded message is incorrect' Sending secret with code DIE to mgr2sol[1] Quitting with result code 1
result:
wrong output format Extra information in the output file