Submission #889

#	Time	Username	Problem	Language	Result	Execution time	Memory
889		tncks0121	Parrots (IOI11_parrots)	C++98	98 / 100	12 ms	2432 KiB

encoder

#include "encoder.h"
#include "encoderlib.h"

int count[1000];

void encode (int N, int M[]) { // 6N approach
	int c1 = 0, c0 = 0;
	for(int i = 0; i < N; i++) {
		for(int j = 0; j < 4; j++) {
			count[i*4+j] = !!(M[i] & 1<<(j*2+1))*2 + !!(M[i] & 1<<(j*2));
			c1 += count[i*4+j];
		}
	}
	c0 = N * 4 * 3 - c1;
	
	if(c1 < c0) {
		for(int i = 0; i < N * 4; i++)
			while(count[i]--) send(i);
	}else {
		send(0); send(0); send(0); send(0);
		for(int i = 0; i < N * 4; i++) {
			count[i] = 3 - count[i];
			while(count[i]--) send(i);
		}
	}
}

decoder

#include "decoder.h"
#include "decoderlib.h"

int count[1000];

void decode (int N, int L, int X[]) {
	int i, j;

	bool isc0 = false; 
	for(i = 0; i < N * 4; i++) count[i] = 0;
	for(i = 0; i < L; i++) {
		++count[X[i]];
		if(count[0] == 4) isc0 = true;
	}

	if(isc0) {
		count[0] -= 4;
		for(i = 0; i < N * 4; i++) count[i] = 3 - count[i];
	}

	for(i = 0; i < N; i++) {
		int ret = 0;
		for(j = 0; j < 4; j++) {
			ret |= count[i * 4 + j] << (2 * j);
		}

		output(ret);
	}

}

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