Submission #359331

#	Time	Username	Problem	Language	Result	Execution time	Memory
359331		Sparky_09	Global Warming (CEOI18_glo)	C++17	100 / 100	70 ms	7040 KiB

glo

#include <bits/stdc++.h>
using namespace std;
#define rep(i, a, b) for(int i = a; i < (b); ++i)
#define all(x) begin(x), end(x)
#define sz(x) (int)(x).size()
typedef long long ll;
typedef pair<ll, ll> pii;
typedef vector<ll> vi;
typedef vector<pii> vpi;

void usaco(string s){
  freopen((s+".in").c_str(), "r", stdin);
  freopen((s+".out").c_str(), "w", stdout);
}

int main() {
  cin.tie(0)->sync_with_stdio(0);
  cin.exceptions(cin.failbit);
#ifdef LOCAL_DEFINE
  freopen("input.txt", "r", stdin);
#endif
  ll n, x, v[200055], dp[200055];
  cin >> n >> x;
  for (int i = 0; i < n; i++) cin >> v[i];
  vector<ll> lis(n, INT_MAX);
  ll k = 0;
  for(int i = 0; i < n; i++){
    int j = lower_bound(lis.begin(), lis.end(), v[i])-lis.begin();
    lis[j] = v[i];
    dp[i] = j+1;
    k = max(k, dp[i]);
  }
  for(ll& i: lis) i = INT_MAX;
  for(int i = n-1; i >= 0; i--){
    int j = lower_bound(lis.begin(), lis.end(), -v[i]+x)-lis.begin();
    int j2 = lower_bound(lis.begin(), lis.end(), -v[i])-lis.begin();
    lis[j2] = -v[i];
    k = max(k, dp[i]+j);
  }
  cout << k << endl;
}
    

Compilation message (stderr)

glo.cpp: In function 'void usaco(std::string)':
glo.cpp:12:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   12 |   freopen((s+".in").c_str(), "r", stdin);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
glo.cpp:13:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   13 |   freopen((s+".out").c_str(), "w", stdout);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 5 / 5
• Subtask 2: 10 / 10
• Subtask 3: 13 / 13
• Subtask 4: 10 / 10
• Subtask 5: 20 / 20
• Subtask 6: 17 / 17
• Subtask 7: 25 / 25