Submission #352042

#	Time	Username	Problem	Language	Result	Execution time	Memory
352042		tengiz05	Parrots (IOI11_parrots)	C++17	99 / 100	8 ms	1584 KiB

encoder

#include "encoder.h"
#include "encoderlib.h"
#include <bits/stdc++.h>
using namespace std;
int A[100];
void encode(int n, int aa[]){
	for(int i=0;i<n;i++)A[i] = aa[i];
	int best_xor = 0;
	for(int j=0;j<8;j++){
		int cnt = 0;
		for(int i=0;i<n;i++){
			cnt += (A[i]>>j&1);
		}if(cnt > n/2)best_xor |= (1<<j);
	}
	send(best_xor);
	send(best_xor);
	send(best_xor);
	send(best_xor);
	for(int i=0;i<n;i++)A[i] ^= best_xor;
	for(int i=0;i<n;i++){
		while(A[i] >= 64){
			A[i] -= 64;
			send(i | (3<<6));
		}
		while(A[i] >= 16){
			A[i] -= 16;
			send(i | (2<<6));
		}
		while(A[i] >= 4){
			A[i] -= 4;
			send(i | (1<<6));
		}
		while(A[i] >= 1){
			A[i] -= 1;
			send(i | (0<<6));
		}
	}
}

decoder

#include "decoder.h"
#include "decoderlib.h"
#include <bits/stdc++.h>
using namespace std;
int a[256], cnt[256];
void decode(int n, int len, int x[]){
	for(int i=0;i<256;i++)a[i]=0,cnt[i]=0;
	for(int i=0;i<len;i++)cnt[x[i]]++;
	int best_xor=0;
	for(int i=0;i<256;i++){
		if(cnt[i] > 3){
			cnt[i] -= 4;
			best_xor = i;
			break;
		}
	}
	for(int i=0;i<len;i++){
		if(!cnt[x[i]])continue;
		int type = (x[i] & 192)>>6;
		int ind = x[i] & 63;
		if(type == 3)a[ind] += 64,cnt[x[i]]--;
		if(!cnt[x[i]])continue;
		if(type == 2)a[ind] += 16,cnt[x[i]]--;
		if(!cnt[x[i]])continue;
		if(type == 1)a[ind] += 4,cnt[x[i]]--;
		if(!cnt[x[i]])continue;
		if(type == 0)a[ind] += 1,cnt[x[i]]--;
		if(!cnt[x[i]])continue;
	}
	for(int i=0;i<n;i++)output(a[i]^best_xor);
}

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