Submission #232956

#	Time	Username	Problem	Language	Result	Execution time	Memory
232956		Zex	Parrots (IOI11_parrots)	C++11	52 / 100	11 ms	1536 KiB

encoder

#include "encoder.h"
#include "encoderlib.h"
#include <bits/stdc++.h>
using namespace std;

int append( int x, int i ){
	return 100*x+i;
}

void encode( int N, int M[] ){
	
	/*	IDEA 3 :
		For every number Mi[ xxxxxxxx ]
		Produce four numbers Ei[ xxxx yy zz ]
		where 0 <= xxxx < 16 , 0 <= yy < 4 , 0 <= zz < 4
			xxxx is i in binary form
			zz is bit 2*yy and bit 2*yy+1 from Mi
	*/

	// for(int i=0;i<N;i++){
	// 	cout << M[i] << ' ' << bitset<8>(M[i]) << endl;
	// }

	for(int i=0;i<N;i++){

		int S = i << 4;
		for(int j=0;j<4;j++){
			int xxxx = i << 4;
			int yy = j << 2;
			bool a = ( M[i] & ( 1 << 2*j ) );
			bool b = ( M[i] & ( 1 << (2*j+1) ) );
			int Sv = xxxx | yy | a | (b<<1);
			send( Sv );
			// std::cout << std::bitset<8>(Sv) << std::endl;
		}

	}

	// std::cout << std::endl;

}

decoder

#include "decoder.h"
#include "decoderlib.h"
#include <bits/stdc++.h>
using namespace std;

void decode(int N, int L, int X[]){
	
	/*	IDEA 3 :
		For every number Mi[ xxxxxxxx ]
		Produce four numbers Ei[ xxxx yy zz ]
		where 0 <= xxxx < 16 , 0 <= yy < 4 , 0 <= zz < 4
			xxxx is i in binary form
			zz is bit 2*yy and bit 2*yy+1 from Mi
	*/

	int A[N] = {};

	for(int i=0;i<L;i++){

		int x = X[i];

		int idx = 0;
		for(int j=7;j>=4;j--) idx |= x & ( 1 << j );

		idx >>= 4;

		int part = 0;
		for(int j=3;j>=2;j--) part |= x & ( 1 << j );

		part >>= 2;

		int msg = 0;

		for(int j=1;j>=0;j--) msg |= x & ( 1 << j );

		A[idx] |= msg << (2*part);

		// std::cout << std::bitset<8>(x) << std::endl;
		// std::cout << std::bitset<4>(idx) << ' ' << std::bitset<2>(part) << ' ' << std::bitset<2>(msg) << std::endl;

	}

	// for(int i=0;i<N;i++) cout << bitset<8>(A[i]) << endl;
	for(int i=0;i<N;i++) output( A[i] );

}

Compilation message (stderr)

encoder.cpp: In function 'void encode(int, int*)':
encoder.cpp:26:7: warning: unused variable 'S' [-Wunused-variable]
   int S = i << 4;
       ^

• Subtask 1: 17 / 17
• Subtask 2: 17 / 17
• Subtask 3: 18 / 18
• Subtask 4: 0 / 29
• Subtask 5: 0 / 19