Submission #1313575

#	Time	Username	Problem	Language	Result	Execution time	Memory
1313575		1ota	Message (IOI24_message)	C++20	Compilation error	0 ms	0 KiB

message

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

#define endl "\n"
#define int long long
#define pii pair<int, int>
#define ff first
#define ss second
#define entire(x) (x).begin(), (x).end()

int n = 1025;

void send_message(vector<bool> m, vector<bool> c){
    reverse(entire(m)); m.push_back(true);
    while ((int) m.size() < n) m.push_back(false);
    reverse(entire(m));

    int fg = 0;
    for (; c[fg] == false; fg++);

    int idx = 0;

    for (int bit = 0; bit < 31; bit++){
        if (bit == fg) continue;
        vector<bool> cur(31, false);
        cur[fg] = c[bit];
        for (int i = fg + 1; i < 31; i++) if (c[i]) cur[i] = m[idx++];
        send_packet(cur);
    }

    while (idx < n){
        vector<bool> cur(31, false);
        for (int i = fg; i < 31 and idx < n; i++) if (c[i]) cur[i] = m[idx++];
        send_packet(cur);
    }

    int len = 0;
    // 1 +  2  + 4  + 8  + 16 = 31 !!
    // 0 -> 1 -> 2 -> 3 -> 4
    for (; (1 << len) < fg; len++) fg -= (1 << len);

    for (int i = 0; i < len; i++){
        vector<bool> cur(n, false);
        if ((1 << i) & fg) fill(entire(cur), true);
        send_packet(cur);
    }
}

// vector<bool> send_packet (vector<bool> a) {

// }

vector<bool> recieve_message (vector<vector<bool>> r){
    // len would always be 66 or more
    int nr = (int) r.size(), len = nr - 66;
    int fg = (1 << len) - 1;
    for (int i = nr - 1; i > nr - 1 - len; i--){
        int cnt1 = count(entire(r[i]), true);
        if (cnt1 >= 16) fg += (1 << (nr - 1 - i));
    }
    
    vector<int> idx{fg};
    vector<bool> c(n, false); c[fg] = true;
    for (int bit = 0; bit < 31; bit++){
        if (bit == fg) continue;
        c[bit] = r[bit - (bit > fg)][fg];
        if (c[bit]) idx.push_back(bit);
    }

    vector<bool> ans;
    for (int i = 0; i < 30; i++){
        for (int bit : idx) if (bit != fg){
            ans.push_back(r[i][bit]);
        }
    }

    for (int i = 30; i < 66; i++){
        for (int bit : idx) ans.push_back(r[i][bit]);
    }

    int fon = 0;
    for (; ans[fon] == false; fon++);

    vector<bool> actual;
    for (int i = fon + 1; i < (int) ans.size(); i++) actual.push_back(ans[i]);

    return actual;
}

Compilation message (stderr)

/usr/bin/ld: /tmp/ccrB73RM.o: in function `(anonymous namespace)::run_decoder()':
stub.cpp:(.text+0x65c): undefined reference to `receive_message(std::vector<std::vector<bool, std::allocator<bool> >, std::allocator<std::vector<bool, std::allocator<bool> > > >)'
collect2: error: ld returned 1 exit status