Submission #351985

#	Time	Username	Problem	Language	Result	Execution time	Memory
351985		juggernaut	Parrots (IOI11_parrots)	C++14	99 / 100	69 ms	1448 KiB

encoder

#include"encoder.h"
#include"encoderlib.h"
#include<bits/stdc++.h>
using namespace std;
void encode(int n,int a[]){
    vector<int>best(n*15,0);
    int sig;
    for(int xr=0;xr<256;xr++){
        vector<int>vec;
        for(int i=0;i<n;i++){
            int x=a[i]^xr;
            for(int j=0;j<8;j++)
				  if(x>>j&1){
				  	if(j%2==1)vec.push_back((i<<2)|(j>>1));
					vec.push_back((i<<2)|(j>>1));
				}
        }
        if(vec.size()<best.size())best=vec,sig=xr;
    }
    for(auto to:best)send(to);
    for(int i=0;i<4;i++)send(sig);
}

decoder

#include"decoder.h"
#include"decoderlib.h"
#include<bits/stdc++.h>
using namespace std;
int res[64],counter[256];
void decode(int n,int m,int a[]){
    for(int i=0;i<n;i++)res[i]=0;
    for(int i=0;i<256;i++)counter[i]=0;
    int mx=0,val;
    for(int i=0;i<m;i++)
        counter[a[i]]++;
    for(int i=0;i<256;i++)if(counter[i]>mx)mx=counter[i],val=i;
    mx=0;
    for(int i=0;i<m;i++){
        if(a[i]==val&&mx!=4){
            mx++;
            continue;
        }
        int data=a[i]&3;
        res[a[i]>>2]+=(1<<(data<<1));
    }
    for(int i=0;i<n;i++)output(res[i]^val);
}

Compilation message (stderr)

encoder.cpp: In function 'void encode(int, int*)':
encoder.cpp:21:29: warning: 'sig' may be used uninitialized in this function [-Wmaybe-uninitialized]
   21 |     for(int i=0;i<4;i++)send(sig);
      |                         ~~~~^~~~~

decoder.cpp: In function 'void decode(int, int, int*)':
decoder.cpp:22:31: warning: 'val' may be used uninitialized in this function [-Wmaybe-uninitialized]
   22 |     for(int i=0;i<n;i++)output(res[i]^val);
      |                         ~~~~~~^~~~~~~~~~~~

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