Submission #1089722

#	Time	Username	Problem	Language	Result	Execution time	Memory
1089722		vjudge1	Xor Sort (eJOI20_xorsort)	C++17	0 / 100	1034 ms	524288 KiB

xorsort

/* https://oj.uz/problem/view/eJOI20_xorsort?locale=en: WA */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <vector>

unsigned int N, S, A[1000];
std::vector<std::pair<unsigned int, unsigned int>> operations;

void destroysort(unsigned int i, unsigned int j) {
  unsigned int split, k, mask;

  if (i == j)
    return;
  for (k = i; k < j-1; ++k)
    if (A[k] > A[k+1])
      goto actually_sort;
  return;
actually_sort:
  for (mask = 0, k = i; k < j; ++k)
    mask |= A[k];
  while (mask & (mask - 1))
    mask &= mask - 1;
  for (k = i; k < j - 1; ++k)
    if ((mask & A[k]) && !(mask & A[k+1])) {
      A[k+1] ^= A[k];
      operations.push_back({k+1, k});
    }
  for (split = i; split < j; ++split)
    if (mask & A[split])
      break;
  destroysort(i, split);
  destroysort(split, j);
}

void cursedbubblesort(unsigned int j) {
  unsigned int i, k;

  if (j == 1)
    return;
  k = 0;
  for (i = 1; i < j; ++i)
    if (A[i] > A[k])
      k = i;
  if (k == j-1) {
    operations.push_back({j-2, j-1});
  } else {
    for (i = k; i < j - 1; ++i)
      operations.push_back({i+1, i});
    for (i = k-1; i > 0; --i)
      operations.push_back({i-1, i});
    for (i = 0; i < j - 1; ++i)
      operations.push_back({i, i+1});
    memmove(&A[k], &A[k+1], sizeof(*A)*(j-k-1));
  }
  cursedbubblesort(j - 1);
}

int main(void) {
  (void) scanf("%u %u", &N, &S);
  for (unsigned int i = 0; i < N; ++i)
    (void) scanf(" %u", &A[i]);
  if (S == 1) {
    for (unsigned int i = 0; i < N - 1; ++i)
      operations.push_back({i, i+1});
    cursedbubblesort(N);
  } else {
    destroysort(0, N);
  }
  printf("%u\n", operations.size());
  for (auto operation : operations)
    printf("%u %u\n", operation.first + 1, operation.second + 1);
  return EXIT_SUCCESS;
}

Compilation message (stderr)

xorsort.cpp: In function 'int main()':
xorsort.cpp:71:12: warning: format '%u' expects argument of type 'unsigned int', but argument 2 has type 'std::vector<std::pair<unsigned int, unsigned int> >::size_type' {aka 'long unsigned int'} [-Wformat=]
   71 |   printf("%u\n", operations.size());
      |           ~^     ~~~~~~~~~~~~~~~~~
      |            |                    |
      |            unsigned int         std::vector<std::pair<unsigned int, unsigned int> >::size_type {aka long unsigned int}
      |           %lu
xorsort.cpp:61:15: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   61 |   (void) scanf("%u %u", &N, &S);
      |          ~~~~~^~~~~~~~~~~~~~~~~
xorsort.cpp:63:17: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   63 |     (void) scanf(" %u", &A[i]);
      |            ~~~~~^~~~~~~~~~~~~~

• Subtask 1: 0 / 25
• Subtask 2: 0 / 35
• Subtask 3: 0 / 40