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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#466867#7689. Flipping CardsWater_OR#WA 1ms5704kbC++171.7kb2024-07-08 11:18:042024-07-08 11:18:05

Judging History

你现在查看的是最新测评结果

  • [2024-07-08 11:18:05]
  • 评测
  • 测评结果:WA
  • 用时:1ms
  • 内存:5704kb
  • [2024-07-08 11:18:04]
  • 提交

answer

#include <bits/stdc++.h>

size_t n;

typedef std::pair<int, int> two;
two input_array[300005];
int worth[300005];

inline bool check(int mid) {
  int counter = 0;
  // std::cout << "# " << mid << "\n|";
  for (size_t i = 0; i < n; ++i) { 
    if (input_array[i].first < mid) { ++counter; }
    if (input_array[i].first < mid && input_array[i].second >= mid) { worth[i] = 1; }
    else if (input_array[i].first >= mid && input_array[i].second < mid) { worth[i] = -1; }
    else { worth[i] = 0; }
    // std::cout << " " << worth[i];
  }
  // std::cout << "\n| " << counter << "\n";
  for (size_t i = 1; i < n; ++i) { worth[i] += worth[i - 1]; }
  int min_index = -1;
  for (size_t i = 0; i < n; ++i) {
    if (worth[i] - (min_index < 0 ? 0 : worth[min_index]) >= counter - n / 2) { return true; }
    if (worth[i] < worth[min_index]) { min_index = i; }
  }
  return false;
}

inline void solve() {
  size_t *index_array;
  index_array = new size_t[n];
  for (size_t i = 0; i < n; ++i) { index_array[i] = i; }
  std::sort(index_array, index_array + n, [=](const size_t &x, const size_t &y) { return input_array[x].first < input_array[y].first; });

  int answer = input_array[index_array[n / 2]].first;
  size_t length = INT32_MAX - answer;
  while (length > 0) {
    size_t half = length - (length >> 1);
    int mid = answer + half;
    if (check(mid)) {
      answer = mid;
      length = length - half;
    } else {
      length = half - 1;
    }
  }
  std::cout << answer << std::endl;
}

signed main() {
  std::cin >> n;
  for (size_t i = 0; i < n; ++i) {
    std::cin >> input_array[i].first >> input_array[i].second;
  }
  solve();
  return 0;
}

Details

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Test #1:

score: 100
Accepted
time: 0ms
memory: 3584kb

input:

5
3 6
5 2
4 7
6 4
2 8

output:

6

result:

ok 1 number(s): "6"

Test #2:

score: 0
Accepted
time: 1ms
memory: 5704kb

input:

1
2 1

output:

2

result:

ok 1 number(s): "2"

Test #3:

score: 0
Accepted
time: 0ms
memory: 3640kb

input:

1
212055293 384338286

output:

384338286

result:

ok 1 number(s): "384338286"

Test #4:

score: -100
Wrong Answer
time: 0ms
memory: 3704kb

input:

99
749159996 323524232
125448341 365892333
481980673 143665393
394405973 44741918
687549448 513811513
287088118 385131171
11865696 666468353
449920567 373650719
671547289 116780561
41003675 671513243
351534153 507850962
374160874 985661954
222519431 600582098
987220654 704142246
856147059 37783620
1...

output:

995384916

result:

wrong answer 1st numbers differ - expected: '528957505', found: '995384916'