Submission #377692

#	Time	Username	Problem	Language	Result	Execution time	Memory
377692		Aldas25	Swimming competition (LMIO18_plaukimo_varzybos)	C++14	100 / 100	435 ms	12080 KiB

plaukimo_varzybos

#pragma GCC optimize("O3")

#include <bits/stdc++.h>

using namespace std;

#define FAST_IO ios_base::sync_with_stdio(0); cin.tie(nullptr)
#define FOR(i, a, b) for(int i = (a); i <= (b); i++)
#define REP(n) FOR(O, 1, (n))
#define pb push_back
#define f first
#define s second
typedef long double ld;
typedef long long ll;
typedef pair<int, int> pii;
typedef pair<int, pii> piii;
typedef vector<int> vi;
typedef vector<pii> vii;
typedef vector<ll> vl;
typedef vector<piii> viii;
//mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

const int MAXN = 1000100, MAXK = 23;
const ll MOD = 1e9+7;
const ll INF = 1e16;
const ld PI = asin(1) * 2;

void setIO () {
    FAST_IO;
}

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

int n, a, b;
int t[MAXN];
bool dp[MAXN];

bool check (int x) {
    int le = 0;
    dp[0] = true;
    FOR(i, 1, n) dp[i] = false;

    FOR(i, a, n) {
        while (le < i-a && (le < i-b || t[i] - t[le+1] > x || !dp[le])) {
            le++;
        }

       // cout << " x = " << x << " i = " << i << " le = " << le << endl;

        if (t[i] - t[le+1] <= x && i-b <= le && le <= i-a && dp[le])
            dp[i] = true;

        //cout <<"   dp = " << dp[i] << endl;
    }

    return dp[n];
}

int main() {
	setIO();

    cin >> n >> a >> b;
    FOR(i, 1, n) cin >> t[i];

    sort(t+1, t+n+1);

    //FOR(i, 0, 10) cout << " i = " << i << " check = " << check(i) << endl;

    int le = 0, ri = 1e7;
    while (le < ri) {
        int mid = (le+ri)/2;
        if (check(mid)) ri = mid;
        else le = mid+1;
    }

    cout << le << "\n";

	return 0;
}

Compilation message (stderr)

plaukimo_varzybos.cpp: In function 'void setIO(std::string)':
plaukimo_varzybos.cpp:34:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   34 |   freopen((s+".in").c_str(),"r",stdin);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
plaukimo_varzybos.cpp:35:9: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   35 |  freopen((s+".out").c_str(),"w",stdout);
      |  ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 20 / 20
• Subtask 3: 30 / 30
• Subtask 4: 40 / 40