Submission #245576

#	Time	Username	Problem	Language	Result	Execution time	Memory
245576		rqi	Holiday (IOI14_holiday)	C++14	100 / 100	2003 ms	22996 KiB

holiday

#include"holiday.h"
#include <bits/stdc++.h>
using namespace std;
 
typedef long long ll;
typedef long double ld;
typedef double db; 
typedef string str; 
 
typedef pair<int,int> pi;
typedef pair<ll,ll> pl; 
typedef pair<db,db> pd; 
 
typedef vector<int> vi; 
typedef vector<ll> vl; 
typedef vector<db> vd; 
typedef vector<str> vs; 
typedef vector<pi> vpi;
typedef vector<pl> vpl; 
typedef vector<pd> vpd; 
 
#define mp make_pair
#define f first
#define s second
#define sz(x) (int)x.size()
#define all(x) begin(x), end(x)
#define rall(x) (x).rbegin(), (x).rend() 
#define rsz resize
#define ins insert 
#define ft front() 
#define bk back()
#define pf push_front 
#define pb push_back
#define eb emplace_back 
#define lb lower_bound 
#define ub upper_bound 
 
#define FOR(i,a,b) for (int i = (a); i < (b); ++i)
#define F0R(i,a) FOR(i,0,a)
#define ROF(i,a,b) for (int i = (b)-1; i >= (a); --i)
#define R0F(i,a) ROF(i,0,a)
#define trav(a,x) for (auto& a: x)
 
const int MOD = 1e9+7; // 998244353;
const int MX = 2e5+5; 
const ll INF = 1e18; 
const ld PI = acos((ld)-1);
const int xd[4] = {1,0,-1,0}, yd[4] = {0,1,0,-1}; 
mt19937 rng((uint32_t)chrono::steady_clock::now().time_since_epoch().count()); 
 
template<class T> bool ckmin(T& a, const T& b) { 
    return b < a ? a = b, 1 : 0; }
template<class T> bool ckmax(T& a, const T& b) { 
    return a < b ? a = b, 1 : 0; } 
int pct(int x) { return __builtin_popcount(x); } 
int bits(int x) { return 31-__builtin_clz(x); } // floor(log2(x)) 
int cdiv(int a, int b) { return a/b+!(a<0||a%b == 0); } // division of a by b rounded up, assumes b > 0 
int fstTrue(function<bool(int)> f, int lo, int hi) {
    hi ++; assert(lo <= hi); // assuming f is increasing
    while (lo < hi) { // find first index such that f is true 
        int mid = (lo+hi)/2; 
        f(mid) ? hi = mid : lo = mid+1; 
    } 
    return lo;
}
 
// INPUT
template<class A> void re(complex<A>& c);
template<class A, class B> void re(pair<A,B>& p);
template<class A> void re(vector<A>& v);
template<class A, size_t SZ> void re(array<A,SZ>& a);
 
template<class T> 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); }
template<class H, class... T> void re(H& h, T&... t) { re(h); re(t...); }
 
template<class A> void re(complex<A>& c) { A a,b; re(a,b); c = {a,b}; }
template<class A, class B> void re(pair<A,B>& p) { re(p.f,p.s); }
template<class A> void re(vector<A>& x) { trav(a,x) re(a); }
template<class A, size_t SZ> void re(array<A,SZ>& x) { trav(a,x) re(a); }
 
// TO_STRING
#define ts to_string
str ts(char c) { return str(1,c); }
str ts(bool b) { return b ? "true" : "false"; }
str ts(const char* s) { return (str)s; }
str ts(str s) { return s; }
template<class A> str ts(complex<A> c) { 
    stringstream ss; ss << c; return ss.str(); }
str ts(vector<bool> v) { 
    str res = "{"; F0R(i,sz(v)) res += char('0'+v[i]);
    res += "}"; return res; }
template<size_t SZ> str ts(bitset<SZ> b) {
    str res = ""; F0R(i,SZ) res += char('0'+b[i]);
    return res; }
template<class A, class B> str ts(pair<A,B> p);
template<class T> str ts(T v) { // containers with begin(), end()
    bool fst = 1; str res = "{";
    for (const auto& x: v) {
        if (!fst) res += ", ";
        fst = 0; res += ts(x);
    }
    res += "}"; return res;
}
template<class A, class B> str ts(pair<A,B> p) {
    return "("+ts(p.f)+", "+ts(p.s)+")"; }
 
// OUTPUT
template<class A> void pr(A x) { cout << ts(x); }
template<class H, class... T> void pr(const H& h, const T&... t) { 
    pr(h); pr(t...); }
void ps() { pr("\n"); } // print w/ spaces
template<class H, class... T> void ps(const H& h, const T&... t) { 
    pr(h); if (sizeof...(t)) pr(" "); ps(t...); }
 
// DEBUG
void DBG() { cerr << "]" << endl; }
template<class H, class... T> void DBG(H h, T... t) {
    cerr << ts(h); if (sizeof...(t)) cerr << ", ";
    DBG(t...); }
#ifdef LOCAL // compile with -DLOCAL
#define dbg(...) cerr << "LINE(" << __LINE__ << ") -> [" << #__VA_ARGS__ << "]: [", DBG(__VA_ARGS__)
#else
#define dbg(...) 0
#endif
 
// FILE I/O
void setIn(string s) { freopen(s.c_str(),"r",stdin); }
void setOut(string s) { freopen(s.c_str(),"w",stdout); }
void unsyncIO() { ios_base::sync_with_stdio(0); cin.tie(0); }
void setIO(string s = "") {
    unsyncIO();
    // cin.exceptions(cin.failbit); 
    // throws exception when do smth illegal
    // ex. try to read letter into int
    if (sz(s)) { setIn(s+".in"), setOut(s+".out"); } // for USACO
}
 
typedef pair<ll, int> T;
/**
 * Description: 1D range update and query, $SZ=2^p$.
 * Source: USACO Counting Haybales
 * Verification: SPOJ Horrible
 */
 
struct LazySeg { 
    int SZ;
    vector<T> sum;
    vl vals;
    vi to;
 
    LazySeg(vl ats) { 
        SZ = 1;
        while(SZ-1 < sz(ats)-1){
            SZ*=2;
        }
 
        to = vi(sz(ats), 0);
        vector<pair<ll, int>> mto;
        for(int i = 0; i < sz(ats); i++){
            mto.pb(mp(ats[i], i));
        }
        sort(all(mto));

        for(int i = 0; i < sz(mto); i++){
            int ind = mto[i].s;
            to[ind] = i;
            vals.pb(mto[i].f);
        }
 
        sum = vector<T>(2*SZ, mp(ll(0), 0));
        for(int i = 0; i < sz(ats); i++){
            int ind = to[i];
            sum[SZ+ind] = mp(0, 0);
        }
    }
 
    T comb(T a, T b){
        return mp(a.f+b.f, a.s+b.s);
    }
    // recalc values for current node
    void pull(int ind) { sum[ind] = comb(sum[2*ind], sum[2*ind+1]); }
    void build() { ROF(i,1,SZ) pull(i); }
    void upd(int i, int on, int ind, int L, int R) {
        assert(L <= i && i <= R);
 
        if (L == i && R == i) { 
            sum[ind].f^=vals[i];
            sum[ind].s^=1;
            assert(sum[ind].s == on); 
            return; 
        }
 
        int M = (L+R)/2; 
        if(i <= M) upd(i, on, 2*ind,L,M); 
        else upd(i, on, 2*ind+1,M+1,R); 
        pull(ind);
    }
 
    void upd(int ind, int on){ //turning on or off
        upd(to[ind], on, 1, 0, SZ-1);
    }
 
    ll topk(int k){ //query sum of the top k
        if(sum[1].s <= k) return sum[1].f;
        T ans = mp(ll(0), 0);
        int ind = 1;
        while(2*ind+1 < 2*SZ){
            if(comb(ans, sum[2*ind+1]).s <= k){
                ans = comb(ans, sum[2*ind+1]);
                ind = 2*ind;
            }
            else{
                ind = 2*ind+1;
            }
        }
        return ans.f;
    }
};

 
 
 
const int mx = 100005;
ll attraction[mx]; //1 indexed
int n, start, d;
 
int c; //cost of travel
vl ats; //1 indexed attractions in 1 direction
vl anses;
LazySeg lseg({});
 
void createanses(int dlo = 0, int dhi = d, int travL = 0, int travR = sz(ats)-1){
	//the topk structure is currently filled up to ats[travL]
	if(dlo > dhi) return;
	int dmid = (dlo+dhi)/2;
	pair<ll, int> ans = mp(-1, -1);
	for(int i = travL; i <= travR; i++){
		int choose = dmid-c*i;
		if(choose < 0) break;
		if(i > travL){
			lseg.upd(i, 1);
		}
		ckmax(ans, mp(lseg.topk(choose), i));
	}

	anses[dmid] = ans.f;

	for(int i = travR; i >= travL; i--){
		int choose = dmid-c*i;
		if(choose < 0) continue;
		if(i == ans.s){
			createanses(dmid+1, dhi, ans.s, travR);
		}
		if(i > travL){
			lseg.upd(i, 0); //reset lseg
		}
	}
	createanses(dlo, dmid-1, travL, ans.s);

}
 
vl solvevard(){ //rval[i] = answer for dvalue = i. C is cost of moving right
	anses = vector<ll>(d+1, 0);
	// if(sz(a) == 1) return ans; //all 0.
 
	// buildtopk with (ats) here
	lseg = LazySeg(ats);
	lseg.upd(0, 1);
	createanses();
 
 	for(int i = 1; i <= d; i++){
 		ckmax(anses[i], anses[i-1]);
 	}
	return anses;
}
 
ll solvefixeddir(){ //left first, then go right
	vl a1, a2;
	a1.pb(0); //make it 1 indexed
	for(int i = start-1; i >= 0; i--){
		a1.pb(attraction[i]);
	}
	a2.pb(0);
	for(int i = start+1; i < n; i++){
		a2.pb(attraction[i]);
	}
 
 	ats = a1;
 	c = 2;
	vl ans1 = solvevard();

	//ps(ats, c, ans1);

	ats = a2;
	c = 1;
	vl ans2 = solvevard();
 
 	ll ans = 0;
	for(int i = 0; i <= d; i++){
		 ckmax(ans, ans1[i]+ans2[d-i]);
	}
	return ans;
}
 
ll solve(){
	// ps(d);

	ll ans1 = solvefixeddir();

	// ps(start);
	// for(int i = 0; i < n; i++){
	// 	cout << attraction[i] << " ";
	// }
	// cout << "\n";
	// ps(ans1);

	for(int i = 0; i < n/2; i++){
		swap(attraction[i], attraction[n-1-i]);
	}
	start = n-1-start;

	ll ans2 = solvefixeddir();

	// ps(start);
	// for(int i = 0; i < n; i++){
	// 	cout << attraction[i] << " ";
	// }
	// cout << "\n";
	// ps(ans2);
	return max(ans1, ans2);
}
 
ll findMaxAttraction(int _n, int _start, int _d, int _attraction[]) {
	n = _n;
	start = _start;
	d = _d;
	for(int i = 0; i < n; i++){
		attraction[i] = _attraction[i];
	}
	if(d == 0) return 0;
	ll ans1 = solve();
	d--;
	ll ans2 = solve()+attraction[start];
 
	return max(ans1, ans2);
}

Compilation message (stderr)

holiday.cpp: In function 'void setIn(std::__cxx11::string)':
holiday.cpp:129:31: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
 void setIn(string s) { freopen(s.c_str(),"r",stdin); }
                        ~~~~~~~^~~~~~~~~~~~~~~~~~~~~
holiday.cpp: In function 'void setOut(std::__cxx11::string)':
holiday.cpp:130:32: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
 void setOut(string s) { freopen(s.c_str(),"w",stdout); }
                         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 7 / 7
• Subtask 2: 23 / 23
• Subtask 3: 17 / 17
• Subtask 4: 53 / 53