Submission #351938

#	Time	Username	Problem	Language	Result	Execution time	Memory
351938		juggernaut	Parrots (IOI11_parrots)	C++14	Compilation error	0 ms	0 KiB

encoder

#include"encoder.h"
#include"encoderlib.h"
#include<bits/stdc++.h>
using namespace std;
int counter[256];
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;
            while(x>63)vec.push_back((i<<2)|3),x-=64;
            while(x>15)vec.push_back((i<<2)|2),x-=16;
            while(x>3)vec.push_back((i<<2)|1),x-=4;
            while(x>0)vec.push_back((i<<2)|0),x-=1;
        }
        if(vec.size()<best.size())best=vec,sig=xr;
    }
    int mx=0;
    for(auto to:best){
        counter[to]++;
        mx=max(mx,counter[to]);
        send(to);
    }
    if(counter[sig])exit(-1);
    for(int i=0;i<=mx;i++)send(sig);
}

decoder

#include "encoder.h"
#include "decoder.h"
#include "encoderlib.h"
#include "decoderlib.h"
#include <stdio.h>
#include <stdlib.h>

#define MAX_N  1000
#define MAX_L 10000

#define CHANNEL_RANGE 65535
#define MAX_EXPANSION 10

static int message[MAX_N];
static int N; // NN;
static int encoded_message[MAX_L];
static int L;
static int output_message[MAX_N];
static int O;

inline
void my_assert(int e){ if (!e) abort(); };

void send(int a)
{
  if(L == MAX_L) {
    printf("Encoded message too long.\n");
    exit(0);
  }
  encoded_message[L] = a;
  L++;
}

void output(int b)
{
  if(O == N)
    O++;
  if(O > N)
    return;
  output_message[O] = b;
  O++;
}

static void shuffle()
{
  int t,i;
  i=0;
  while(i < L-1) {
    t = encoded_message[i];
    encoded_message[i] = encoded_message[i+1];
    encoded_message[i+1] = t;
    i += 2;
  }
}

static void check_encoded_message()
{
  int i;
  if(L > MAX_EXPANSION * N) {
    printf("Encoded message too long.");
    exit(0);
  }
  for(i=0; i < L; i++)
    if((encoded_message[i] < 0) || 
       (encoded_message[i] > CHANNEL_RANGE)) {
      printf("Bad encoded integer.\n");
      exit(0);
    }
}

static int check_output()
{
  int i;

  if(O!=N)
    return 0;
  for(i = 0; i < N; i++)
    if(message[i] != output_message[i])
      return 0;
  return 1;
}

int main()
{
  int i,t;
  double ratio;

  my_assert(1==scanf("%d",&N));
  for(i = 0; i < N; i++)
    my_assert(1==scanf("%d",&message[i]));

  ratio = 0;

  for(t=0; t<2; t++) {
    L = 0;
    encode(N,message);

    check_encoded_message();

    if((double) L / N > ratio)
      ratio = ((double)L)/N;
    
    if(t==1)
      shuffle();
  
    // NN = 0;
    O = 0;
    decode(N,L,encoded_message);

    if(!check_output()) {
      printf("Incorrect.\n");
      exit(0);
    }
  }
  printf("Correct.\n");
  fprintf(stderr,"Ratio = %3.3f\n",ratio);

  return 0;
}

Compilation message (stderr)

encoder.cpp: In function 'void encode(int, int*)':
encoder.cpp:27:31: warning: 'sig' may be used uninitialized in this function [-Wmaybe-uninitialized]
   27 |     for(int i=0;i<=mx;i++)send(sig);
      |                           ~~~~^~~~~

/tmp/ccazaSLS.o: In function `output(int)':
decoder.cpp:(.text+0x50): multiple definition of `output(int)'
/tmp/ccCQqO59.o:grader_decoder.cpp:(.text+0x40): first defined here
/tmp/ccazaSLS.o: In function `main':
decoder.cpp:(.text.startup+0x0): multiple definition of `main'
/tmp/ccCQqO59.o:grader_decoder.cpp:(.text.startup+0x0): first defined here
/tmp/ccazaSLS.o: In function `main':
decoder.cpp:(.text.startup+0x93): undefined reference to `encode(int, int*)'
decoder.cpp:(.text.startup+0x12e): undefined reference to `decode(int, int, int*)'
/tmp/ccCQqO59.o: In function `main':
grader_decoder.cpp:(.text.startup+0x21f): undefined reference to `decode(int, int, int*)'
collect2: error: ld returned 1 exit status