oj.uz

Submission #699701

# Submission time Handle Problem Language Result Execution time Memory
699701 2023-02-17T19:54:44 Z Zflop Hacker (BOI15_hac) C++14
100 / 100
 311 ms 18392 KB 
#include <bits/stdc++.h>
using namespace std;

/*
ID: 10002181
LANG: C++
TASK: lamps
*/

using str = string; // yay python!
using ld = long double; // or double, if TL is tight
using ll = long long;
using int64 = ll;
using db = double;
using ull = unsigned long long;

#define ch() getchar()
#define pc(x) putchar(x)
#define tcT template<class T
#define tcTU tcT, class U
tcT> using V = vector<T>;
tcT, size_t SZ> using AR = array<T,SZ>;
using vi = V<int>;
using vb = V<bool>;
using vpi = V<pair<int,int>>;
using vvi = V<vi>;
using vl = V<ll>;
using vd = V<ld>;
using vstr = V<str>;

#define all(x) begin(x), end(x)
#define sor(x) sort(all(x))
#define rev(x) reverse(all(x))
#define sz(x) (int)(x).size()
#define rall(x) x.rbegin(), x.rend()
#define AR array

// loops
#define F0R(i, a, b) for (int i=a; i<b;++i)
#define FOR(i, a) for (int i=0; i<a;++i)
#define FORn(i, a) for (int i=1; i<=a;++i)
#define ROF(i,a) for(int i=a-1; i >= 0;--i)
#define R0F(i,a,b) for(int i=a; i > b;--i)
#define ROFn(i,a) for(int i=a; i > 0;--i)
#define rep(a) F0R(_, a)
#define trav(i,x) for(auto& i:x)

// pairs
#define mp make_pair
#define pi pair <int, int>
#define f first
#define s second

// vectors
#define lb lower_bound
#define ub upper_bound
#define SUM(v) accumulate(all(v), 0LL)
#define MN(v) *min_element(all(v))
#define MX(v) *max_element(all(v))
#define UNIQUE(a) (a).erase(unique((a).begin(),(a).end()),(a).end())
#define eb emplace_back
#define ft front()
#define bk back()
#define ins insert
#define pf push_front
#define pb push_back
#define emt empty()
#define rsz resize

#define pob pop_back()
#define pof pop_front()

#define swp(a,b) a^=b^=a^=b

#define ts to_string

#define setIO()  ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL)

const ll MOD = 1e9+7;
const ll MAX = 100000000000;
const ll INF = 1e18; // not too close to LLONG_MAX
const ld PI = acos((ld)-1);

#ifdef _DEBUG
    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);
#endif

const int dx[4] = {1,0,-1,0}, dy[4] = {0,1,0,-1}; // for every grid problem!!

tcT> bool ckmin(T& a, const T& b) {
	return b < a ? a = b, 1 : 0; } // set a = min(a,b)
tcT> bool ckmax(T& a, const T& b) {
	return a < b ? a = b, 1 : 0; }

tcTU> T fstTrue(T lo, T hi, U f) {
	hi ++; assert(lo <= hi); // assuming f is increasing
	while (lo < hi) { // find first index such that f is true
		T mid = lo+(hi-lo)/2;
		f(mid) ? hi = mid : lo = mid+1;
	}
	return lo;
}
tcTU> T lstTrue(T lo, T hi, U f) {
	lo --; assert(lo <= hi); // assuming f is decreasing
	while (lo < hi) { // find first index such that f is true
		T mid = lo+(hi-lo+1)/2;
		f(mid) ? lo = mid : hi = mid-1;
	}
	return lo;
}

//INPUT
#define tcTUU tcT, class ...U
tcT> void re(complex<T>& c);
tcTU> void re(pair<T,U>& p);
tcT> void re(V<T>& v);
tcT, size_t SZ> void re(AR<T,SZ>& a);

tcT> void re(T& x) { cin >> x; }
void re(db& d) { str t; re(t); d = stod(t); }
void re(ld& d) { str t; re(t); d = stold(t); }
tcTUU> void re(T& t, U&... u) { re(t); re(u...); }

tcT> void re(complex<T>& c) { T a,b; re(a,b); c = {a,b}; }
tcTU> void re(pair<T,U>& p) { re(p.f,p.s); }
tcT> void re(V<T>& x) { trav(a,x) re(a); }
tcT> void rv(int n, V<T>& x) { x.rsz(n); re(x); }

//OUTPUT
namespace output {
	tcT> void PS(V<T>& x) { FOR(i,sz(x)) cout << x[i] << " \n"[i + 1 == sz(x)];}
	tcT> void PS(bool ok) { if(ok) cout << "YES\n"; else cout << "NO\n"; }
    template<class T1, class T2> void pr(const pair<T1,T2>& x);
    tcT, size_t SZ> void pr(const array<T,SZ>& x);
    tcT> void pr(const vector<T>& x);
    tcT> void pr(const set<T>& x);
    template<class T1, class T2> void pr(const map<T1,T2>& x);

    tcT> void pr(const T& x) { cout << x; }
    template<class Arg, class... Args> void pr(const Arg& first, const Args&... rest) {
        pr(first); pr(rest...);
    }

    template<class T1, class T2> void pr(const pair<T1,T2>& x) {
        pr("{",x.f,", ",x.s,"}");
    }
    tcT> void prContain(const T& x) {
        pr("{");
        bool fst = 1; trav(a,x) pr(!fst?", ":"",a), fst = 0;
        pr("}");
    }
    tcT, size_t SZ> void pr(const array<T,SZ>& x) { prContain(x); }
    tcT> void pr(const vector<T>& x) { prContain(x); }
    tcT> void pr(const set<T>& x) { prContain(x); }
    template<class T1, class T2> void pr(const map<T1,T2>& x) { prContain(x); }

    void ps() { pr("\n"); } // print w/ spaces
    template<class Arg> void ps(const Arg& first) { pr(first,"\n"); }
    template<class Arg, class... Args> void ps(const Arg& first, const Args&... rest) {
        pr(first," "); ps(rest...);
    }
}

using namespace output;

template <int MOD_> struct modnum {
	static constexpr int MOD = MOD_;
	static_assert(MOD_ > 0, "MOD must be positive");
 
private:
	using ll = long long;
 
	int v;
 
	static int minv(int a, int m) {
		a %= m;
		assert(a);
		return a == 1 ? 1 : int(m - ll(minv(m, a)) * ll(m) / a);
	}
 
public:
 
	modnum() : v(0) {}
	modnum(ll v_) : v(int(v_ % MOD)) { if (v < 0) v += MOD; }
	explicit operator int() const { return v; }
	friend std::ostream& operator << (std::ostream& out, const modnum& n) { return out << int(n); }
	friend std::istream& operator >> (std::istream& in, modnum& n) { ll v_; in >> v_; n = modnum(v_); return in; }
 
	friend bool operator == (const modnum& a, const modnum& b) { return a.v == b.v; }
	friend bool operator != (const modnum& a, const modnum& b) { return a.v != b.v; }
 
	modnum inv() const {
		modnum res;
		res.v = minv(v, MOD);
		return res;
	}
	friend modnum inv(const modnum& m) { return m.inv(); }
	modnum neg() const {
		modnum res;
		res.v = v ? MOD-v : 0;
		return res;
	}
	friend modnum neg(const modnum& m) { return m.neg(); }
 
	modnum operator- () const {
		return neg();
	}
	modnum operator+ () const {
		return modnum(*this);
	}
 
	modnum& operator ++ () {
		v ++;
		if (v == MOD) v = 0;
		return *this;
	}
	modnum& operator -- () {
		if (v == 0) v = MOD;
		v --;
		return *this;
	}
	modnum& operator += (const modnum& o) {
		v += o.v;
		if (v >= MOD) v -= MOD;
		return *this;
	}
	modnum& operator -= (const modnum& o) {
		v -= o.v;
		if (v < 0) v += MOD;
		return *this;
	}
	modnum& operator *= (const modnum& o) {
		v = int(ll(v) * ll(o.v) % MOD);
		return *this;
	}
	modnum& operator /= (const modnum& o) {
		return *this *= o.inv();
	}
 
	friend modnum operator ++ (modnum& a, int) { modnum r = a; ++a; return r; }
	friend modnum operator -- (modnum& a, int) { modnum r = a; --a; return r; }
	friend modnum operator + (const modnum& a, const modnum& b) { return modnum(a) += b; }
	friend modnum operator - (const modnum& a, const modnum& b) { return modnum(a) -= b; }
	friend modnum operator * (const modnum& a, const modnum& b) { return modnum(a) *= b; }
	friend modnum operator / (const modnum& a, const modnum& b) { return modnum(a) /= b; }
};

void setF(string fileName = "") {
	ios_base::sync_with_stdio(0); cin.tie(0);
	if((int)fileName.size()) {
		freopen((fileName+".in").c_str(), "r", stdin);
		freopen((fileName+".out").c_str(), "w", stdout);
	}
}

vi SIEVE(int N){ // sieve in O(N)
	vi pr;
	vb b(N);
	vi g(N);
	F0R(i,2,N){
		if(!b[i]){
			pr.pb(i);
			for (int j = i + i; j < N; j += i) b[j] = true;
			}
		}
	return pr;
	}

struct DSU {
	vector<int> e;
	DSU(int N) { e = vector<int>(N, -1); }

	int get(int x) { return e[x] < 0 ? x : e[x] = get(e[x]); }

	bool same_set(int a, int b) { return get(a) == get(b); }

	int size(int x) { return -e[get(x)]; }

	bool unite(int x, int y) {  // union by size
		x = get(x), y = get(y);
		if (x == y) return false;
		if (e[x] > e[y]) swap(x, y);
		e[x] += e[y]; e[y] = x;
		return true;
	}
};

struct edge{
	int a;
	int b;
	int w;
	};

ll POW(ll x, ll y,ll mod = INF){
    ll res = 1LL;
    x %= mod;
    while(y){
        if (y & 1LL)
            res *= x;
        res %= mod;
        x = (x*x) % mod;
        y >>= 1LL;
    }
    return res;
}

ll gauss(ll n) { return n * (n + 1ll) / 2; }

ll fact(ll x) { if(x) return x * fact(x - 1ll); return 1; }

vl fc;
void F(int N,ll MOD){
	fc.rsz(N + 1);
	fc[0] = 1;
	FORn(i,N) fc[i] = fc[i - 1] * i * 1ll % MOD;
	}
	
vl inv;
void I(int N,ll MOD){
	inv.rsz(N + 1);
	inv[N] = POW(fc[N],MOD - 2,MOD);
	for (int i = N; i ;--i) inv[i - 1] = inv[i] * 1ll * i % MOD;
	}

ll Cr(ll N,ll K,ll mod){
	if(K < 0) return 0;
	if(K > N) return 0;
	return fc[N] * 1ll * inv[K] % mod * inv[N - K] % mod;
	}

/*
 scanf("%lld", &testInteger);
 printf("%lld", testInteger);

 ____ ____ ____ ____ ____  ____
||f |||l |||o |||p |||p ||||y ||
||__|||__|||__|||__|||__||||__||
|/__\|/__\|/__\|/__\|/__\||/__\|

**/
void solve() {
	int N; cin >> N;
	vi A(N); re(A);
	int sm = SUM(A);
	FOR(i,N - 1) A.pb(A[i]);
	int n = N;
	N = sz(A);
	multiset<int>m;
	int ans = 0;
	F0R(i,1,N) A[i] += A[i - 1];
	
	int d = n / 2;
	//ps(A);
	for (int i = d - 1; i < n - 1;++i) m.ins(A[i] - (i >= d ? A[i - d] : 0));
	//trav(x,m) cout << x << ' ';
	//cout << '\n' << "NU";
	for(int i = 0; i <= N - n;++i){
		//ps(A[i + d - 1] - (i ? A[i - 1] : 0),A[i + n - 1] - A[i + n - d - 1],i,d,n);
		m.erase(m.find(A[i + d - 1] - (i ? A[i - 1] : 0)));
		m.ins(A[i + n - 1] - A[i + n - d - 1]);
		ckmax(ans,sm - *--m.end());
		//trav(x,m) cout << x << ' ';
		//cout << '\n';
		//ps(*--m.end());
		}
	ps(ans);
}		 
main()
{   setIO();
	solve();
}
// look out for out of bounds arrays
// And more importantly, is y a vowel? Damian:1
// <3 :L ._. <_<
// You have no idea how high I can fly

Compilation message

hac.cpp:369:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
  369 | main()
      | ^~~~
hac.cpp: In function 'void setF(std::string)':
hac.cpp:252:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  252 |   freopen((fileName+".in").c_str(), "r", stdin);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
hac.cpp:253:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  253 |   freopen((fileName+".out").c_str(), "w", stdout);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 1 ms 212 KB Output is correct
4 Correct 0 ms 212 KB Output is correct
5 Correct 1 ms 320 KB Output is correct
6 Correct 0 ms 212 KB Output is correct
7 Correct 0 ms 212 KB Output is correct
8 Correct 1 ms 212 KB Output is correct
9 Correct 0 ms 212 KB Output is correct
10 Correct 1 ms 212 KB Output is correct
11 Correct 1 ms 212 KB Output is correct
12 Correct 1 ms 212 KB Output is correct
13 Correct 1 ms 212 KB Output is correct
14 Correct 1 ms 316 KB Output is correct
15 Correct 1 ms 212 KB Output is correct
16 Correct 1 ms 212 KB Output is correct
17 Correct 1 ms 212 KB Output is correct
18 Correct 1 ms 212 KB Output is correct

Subtask #2
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 1 ms 212 KB Output is correct
4 Correct 0 ms 212 KB Output is correct
5 Correct 1 ms 320 KB Output is correct
6 Correct 0 ms 212 KB Output is correct
7 Correct 0 ms 212 KB Output is correct
8 Correct 1 ms 212 KB Output is correct
9 Correct 0 ms 212 KB Output is correct
10 Correct 1 ms 212 KB Output is correct
11 Correct 1 ms 212 KB Output is correct
12 Correct 1 ms 212 KB Output is correct
13 Correct 1 ms 212 KB Output is correct
14 Correct 1 ms 316 KB Output is correct
15 Correct 1 ms 212 KB Output is correct
16 Correct 1 ms 212 KB Output is correct
17 Correct 1 ms 212 KB Output is correct
18 Correct 1 ms 212 KB Output is correct
19 Correct 1 ms 340 KB Output is correct
20 Correct 1 ms 324 KB Output is correct
21 Correct 1 ms 340 KB Output is correct
22 Correct 1 ms 332 KB Output is correct
23 Correct 2 ms 492 KB Output is correct
24 Correct 1 ms 340 KB Output is correct
25 Correct 2 ms 468 KB Output is correct
26 Correct 2 ms 468 KB Output is correct
27 Correct 0 ms 212 KB Output is correct
28 Correct 1 ms 212 KB Output is correct
29 Correct 1 ms 320 KB Output is correct
30 Correct 2 ms 456 KB Output is correct
31 Correct 2 ms 468 KB Output is correct

Subtask #3
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 1 ms 212 KB Output is correct
3 Correct 3 ms 468 KB Output is correct
4 Correct 31 ms 3096 KB Output is correct
5 Correct 84 ms 7220 KB Output is correct
6 Correct 117 ms 9228 KB Output is correct
7 Correct 132 ms 11056 KB Output is correct
8 Correct 311 ms 18088 KB Output is correct

Subtask #4
40.0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 1 ms 212 KB Output is correct
4 Correct 0 ms 212 KB Output is correct
5 Correct 1 ms 320 KB Output is correct
6 Correct 0 ms 212 KB Output is correct
7 Correct 0 ms 212 KB Output is correct
8 Correct 1 ms 212 KB Output is correct
9 Correct 0 ms 212 KB Output is correct
10 Correct 1 ms 212 KB Output is correct
11 Correct 1 ms 212 KB Output is correct
12 Correct 1 ms 212 KB Output is correct
13 Correct 1 ms 212 KB Output is correct
14 Correct 1 ms 316 KB Output is correct
15 Correct 1 ms 212 KB Output is correct
16 Correct 1 ms 212 KB Output is correct
17 Correct 1 ms 212 KB Output is correct
18 Correct 1 ms 212 KB Output is correct
19 Correct 1 ms 340 KB Output is correct
20 Correct 1 ms 324 KB Output is correct
21 Correct 1 ms 340 KB Output is correct
22 Correct 1 ms 332 KB Output is correct
23 Correct 2 ms 492 KB Output is correct
24 Correct 1 ms 340 KB Output is correct
25 Correct 2 ms 468 KB Output is correct
26 Correct 2 ms 468 KB Output is correct
27 Correct 0 ms 212 KB Output is correct
28 Correct 1 ms 212 KB Output is correct
29 Correct 1 ms 320 KB Output is correct
30 Correct 2 ms 456 KB Output is correct
31 Correct 2 ms 468 KB Output is correct
32 Correct 1 ms 212 KB Output is correct
33 Correct 1 ms 212 KB Output is correct
34 Correct 3 ms 468 KB Output is correct
35 Correct 31 ms 3096 KB Output is correct
36 Correct 84 ms 7220 KB Output is correct
37 Correct 117 ms 9228 KB Output is correct
38 Correct 132 ms 11056 KB Output is correct
39 Correct 311 ms 18088 KB Output is correct
40 Correct 4 ms 596 KB Output is correct
41 Correct 7 ms 980 KB Output is correct
42 Correct 11 ms 1364 KB Output is correct
43 Correct 94 ms 7348 KB Output is correct
44 Correct 274 ms 18092 KB Output is correct
45 Correct 45 ms 3788 KB Output is correct
46 Correct 127 ms 10968 KB Output is correct
47 Correct 284 ms 18044 KB Output is correct
48 Correct 239 ms 18392 KB Output is correct
49 Correct 201 ms 17460 KB Output is correct
50 Correct 203 ms 17444 KB Output is correct