Submission #821386

#	Time	Username	Problem	Language	Result	Execution time	Memory
821386		PixelCat	Bit Shift Registers (IOI21_registers)	C++17	89 / 100	3 ms	1044 KiB

registers

#include "registers.h"

#ifdef NYAOWO
#include "grader.cpp"
#endif

#include <bits/stdc++.h>
#define For(i, a, b) for(int i = a; i <= b; i++)
#define Forr(i, a, b) for(int i = a; i >= b; i--)
#define F first
#define S second
#define sz(x) ((int)x.size())
#define all(x) x.begin(), x.end()
#define eb emplace_back
// #define int LL
using namespace std;
using i32 = int32_t;
using LL = long long;
using pii = pair<int, int>;

// #define DEBUG
#ifdef DEBUG
#define PRINT(x) append_print(x)
#else
#define PRINT(x)
#endif

/*

function signatures:
  void append_move(int t, int x)
  void append_store(int t, std::vector<bool> v)
  void append_and(int t, int x, int y)
  void append_or(int t, int x, int y)
  void append_xor(int t, int x, int y)
  void append_not(int t, int x)
  void append_left(int t, int x, int p)
  void append_right(int t, int x, int p)
  void append_add(int t, int x, int y)
  void append_print(int t)

registers:
  0  input/output
  1  input/output (shifted right for k bits)
  2  mask for useful segments (every other numbers)
  3  mask for first bits of every useful segments
  4  (m[0] ^ m[1]) & m[2] (XORs of adjacent numbers)
  5  hi-bit of XORs of adjacent numbers
  6  m[0] & m[5] (should this pair be swapped?)
  7  'expanded' m[6]
  8  m[7] & m[4] (swapping key for every pair of numbers)

*/

void make_sorter(int n, int k) {
    auto expand_right = [&](int r, int cnt) {
        int j = 1;
        while(j < cnt) {
            int j2 = min(j * 2, cnt) - j;
            append_right(49, r, j2);
            append_or(r, r, 49);
            j += j2;
        }
    };

    // s = 0 or 1
    auto make_masks = [&](int s) {
        vector<bool> m2(2000, 0);
        vector<bool> m3(2000, 0);
        for(int i = s; i < n - 1; i += 2) {
            m3[i * k] = 1;
            For(j, 0, k - 1) m2[i * k + j] = 1;
        }
        append_store(2, m2);
        append_store(3, m3);
    };

    int parity = 1;
    For(_, 0, n) {
        parity = 1 - parity;
        make_masks(parity);
        append_right(1, 0, k);
        append_xor(4, 0, 1);
        append_and(4, 4, 2);  // 5

        append_move(5, 4);
        expand_right(5, k);
        append_and(5, 5, 2);
        append_add(5, 5, 3);
        append_right(5, 5, 1);  // 12

        append_and(6, 0, 5);
        append_left(7, 6, k - 1);
        expand_right(7, k * 2 - 1);  // 12

        append_and(8, 7, 4);
        append_xor(0, 0, 8);
        append_left(8, 8, k);
        append_xor(0, 0, 8);  // 4
    }
}

void make_min(int n, int k) {
    auto make_masks = [&](int i) {
        vector<bool> m_one(2000, 0), m_all(2000, 0), m_negall(2000, 1);
        m_one[i] = 1;
        for(int j = i; j < n * k; j += k) {
            m_all[j] = 1;
            m_negall[j] = 0;
        }
        For(j, 0, i - 1) m_negall[j] = 0;
        m_negall[i] = 1;
        append_store(2, m_one);
        append_store(3, m_all);
        append_store(4, m_negall);
    };

    Forr(i, k - 1, 0) {
        make_masks(i);  // = 3 operations

        // extract all ppl
        append_and(5, 0, 3);
        append_add(6, 4, 5);
        append_right(8, 6, 1000);
        append_not(7, 8);  // = 7 operations

        // update answer
        append_and(2, 2, 7);
        append_or(1, 1, 2);  // = 9 operations

        if(!i) break;

        // kill bad guys
        append_and(5, 5, 8);
        append_or(9, 5, 9);
        append_right(9, 9, 1);
        append_or(0, 0, 9);
    }
    append_move(0, 1);
}

void construct_instructions(int s, int n, int k, int q) {
    if(s == 1) make_sorter(n, k);
    else       make_min(n, k);
}

/*

0 2 1 1000
0 0
0 1
1 0
1 1
-1

move 1 0
right 1 1 1
and 0 0 1
0
0
0
1


1 2 1 1000
0 0
0 1
1 0
1 1
-1

move 1 0
right 1 1 1
and 2 0 1
or 3 0 1
left 3 3 1
or 0 2 3
0 0
0 1
0 1
1 1

*/

• Subtask 1: 10 / 10
• Subtask 2: 0 / 11
• Subtask 3: 12 / 12
• Subtask 4: 25 / 25
• Subtask 5: 13 / 13
• Subtask 6: 29 / 29