Submission #1034232

#	Time	Username	Problem	Language	Result	Execution time	Memory
1034232		vjudge1	cmp (balkan11_cmp)	C++17	0 / 100	436 ms	82340 KiB

cmp

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

const int inf = INT_MAX;

int a[4096], b[2][64];

void remember(int n) {
  for (int i = 0; i < 4096; i++) {
    a[i] = -2;
    b[0][i] = inf;
    b[1][i] = -inf;
  }

  int x = __builtin_popcount(n);
  if (x <= 1 + 12-x) {
    for (int i = 0; i <= 11; i++) {
      if ((n >> i) & 1) bit_set(i+1);
    }
  }
  else {
    bit_set(13);
    for (int i = 0; i <= 11; i++) {
      if (!((n >> i) & 1)) bit_set(i+1);
    }
  }
}

void update(int x, int y) {
  a[x] = y;
  b[0][x/64] = min(b[0][x/64], y);
  b[1][x/64] = max(b[1][x/64], y);
}

int compare(int n) {
  if (n && a[n-1] == 1 && n+1 < 4096 && a[n+1] == -1) {
    update(n, 0);
    return 0;
  }

  for (int i = 0; i < n; i++) {
    if (i%64 == 0 && i+63 < n) {
      if (b[0][i/64] < 1) {
        update(n, -1);
        return -1;
      }

      i += 63;
      continue;
    }

    if (a[i] == -2) continue;
    else if (a[i] < 1) {
      update(n, -1);
      return -1;
    }
  }

  for (int i = 0; i < n; i++) {
    if (i%64 == 0 && i+63 < n) {
      if (b[1][i/64] > -1) {
        update(n, 1);
        return 1;
      }

      i += 63;
      continue;
    }

    if (a[i] == -2) continue;
    else if (a[i] > -1) {
      update(n, 1);
      return 1;
    }
  }

  int inv = bit_get(13);
  for (int i = 11; i >= 0; i--) {
    int x = bit_get(i+1);
    if (inv) x = !x;

    int y = (n >> i) & 1;
    
    if (x > y) return -1;
    else if (x < y) return 1;
  }

  return 0;
}

Compilation message (stderr)

cmp.cpp: In function 'void remember(int)':
cmp.cpp:12:13: warning: iteration 64 invokes undefined behavior [-Waggressive-loop-optimizations]
   12 |     b[0][i] = inf;
      |     ~~~~~~~~^~~~~
cmp.cpp:10:21: note: within this loop
   10 |   for (int i = 0; i < 4096; i++) {
      |                   ~~^~~~~~

• Subtask 1: 0 / 100