Submission #319609

#	Time	Username	Problem	Language	Result	Execution time	Memory
319609		rqi	Sails (IOI07_sails)	C++14	100 / 100	267 ms	5484 KiB

sails

#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<bool> vb; 
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 sor(x) sort(all(x)) 
#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; } 
constexpr int pct(int x) { return __builtin_popcount(x); } 
constexpr int bits(int x) { return 31-__builtin_clz(x); } // floor(log2(x)) 
ll cdiv(ll a, ll b) { return a/b+((a^b)>0&&a%b); } // divide a by b rounded up
ll fdiv(ll a, ll b) { return a/b-((a^b)<0&&a%b); } // divide a by b rounded down
ll half(ll x) { return fdiv(x,2); }

template<class T, class U> T fstTrue(T lo, T hi, U f) { 
	// note: if (lo+hi)/2 is used instead of half(lo+hi) then this will loop infinitely when lo=hi
	hi ++; assert(lo <= hi); // assuming f is increasing
	while (lo < hi) { // find first index such that f is true 
		T mid = half(lo+hi);
		f(mid) ? hi = mid : lo = mid+1; 
	} 
	return lo;
}
template<class T, class U> 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 = half(lo+hi+1);
		f(mid) ? lo = mid : hi = mid-1;
	} 
	return lo;
}
template<class T> void remDup(vector<T>& v) { 
	sort(all(v)); v.erase(unique(all(v)),end(v)); }

// 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(const char* s) { return (str)s; }
str ts(str s) { return s; }
str ts(bool b) { 
	#ifdef LOCAL
		return b ? "true" : "false"; 
	#else 
		return ts((int)b);
	#endif
}
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()
	#ifdef LOCAL
		bool fst = 1; str res = "{";
		for (const auto& x: v) {
			if (!fst) res += ", ";
			fst = 0; res += ts(x);
		}
		res += "}"; return res;
	#else
		bool fst = 1; str res = "";
		for (const auto& x: v) {
			if (!fst) res += " ";
			fst = 0; res += ts(x);
		}
		return res;

	#endif
}
template<class A, class B> str ts(pair<A,B> p) {
	#ifdef LOCAL
		return "("+ts(p.f)+", "+ts(p.s)+")"; 
	#else
		return ts(p.f)+" "+ts(p.s);
	#endif
}

// 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, chk -> fake assert
	#define dbg(...) cerr << "Line(" << __LINE__ << ") -> [" << #__VA_ARGS__ << "]: [", DBG(__VA_ARGS__)
	#define chk(...) if (!(__VA_ARGS__)) cerr << "Line(" << __LINE__ << ") -> function(" \
		 << __FUNCTION__  << ") -> CHK FAILED: (" << #__VA_ARGS__ << ")" << "\n", exit(0);
#else
	#define dbg(...) 0
	#define chk(...) 0
#endif

// FILE I/O
void setIn(str s) { freopen(s.c_str(),"r",stdin); }
void setOut(str s) { freopen(s.c_str(),"w",stdout); }
void unsyncIO() { cin.tie(0)->sync_with_stdio(0); }
void setIO(str 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
}

const int SZ = 131072;

/**
 * Description: 1D range increment and sum query.
 * Source: USACO Counting Haybales
 * Verification: SPOJ Horrible
 */

template<class T> struct LazySeg { 
	static_assert(pct(SZ) == 1); // SZ must be power of 2
	const T ID = mp(MOD, -MOD); //min, max 
	T comb(T a, T b) {
		return mp(min(a.f, b.f), max(a.s, b.s));
	}
	T seg[2*SZ];
	int lazy[2*SZ]; 
	LazySeg() { 
		F0R(i,2*SZ){
			seg[i] = mp(0, 0); 
			lazy[i] = 0;
		}
	}
	void push(int ind, int L, int R) { /// modify values for current node
		seg[ind].f += lazy[ind]; // dependent on operation
		seg[ind].s += lazy[ind];
		if (L != R) F0R(i,2) lazy[2*ind+i] += lazy[ind]; /// prop to children
		lazy[ind] = 0; 
	} // recalc values for current node
	void pull(int ind) { seg[ind] = comb(seg[2*ind],seg[2*ind+1]); }
	void build() { ROF(i,1,SZ) pull(i); }
	void upd(int lo,int hi, int inc,int ind=1,int L=0, int R=SZ-1) {
		push(ind,L,R); if (hi < L || R < lo) return;
		if (lo <= L && R <= hi) { 
			lazy[ind] = inc; push(ind,L,R); return; }
		int M = (L+R)/2; upd(lo,hi,inc,2*ind,L,M); 
		upd(lo,hi,inc,2*ind+1,M+1,R); pull(ind);
	}
	T query(int lo, int hi, int ind=1, int L=0, int R=SZ-1) {
		push(ind,L,R); if (lo > R || L > hi) return ID;
		if (lo <= L && R <= hi) return seg[ind];
		int M = (L+R)/2; 
		return comb(query(lo,hi,2*ind,L,M),query(lo,hi,2*ind+1,M+1,R));
	}

	pi getRang(int val, int ind=1, int L=0, int R=SZ-1) {
		push(ind, L, R); if(seg[ind].s < val || seg[ind].f > val) return mp(-1, -1);
		if(seg[ind].f == seg[ind].s){
			return mp(L, R);
		}
		int M = (L+R)/2;

		pi q1 = getRang(val, 2*ind, L, M);
		pi q2 = getRang(val, 2*ind+1, M+1, R);

		if(q1 == mp(-1, -1)) return q2;
		if(q2 == mp(-1, -1)) return q1;

		return mp(q1.f, q2.s);
	}
};

LazySeg<pi> lseg;

const int mx = 100005;
int H[mx];
int K[mx];

int main() {
	setIO();
	int N;
	cin >> N;
	vpi sails;
	for(int i = 1; i <= N; i++){
		int H, K;
		cin >> H >> K;
		sails.pb(mp(H, K));
	}
	sort(all(sails));

	for(auto u: sails){
		int h = u.f;
		int k = u.s;
		int L = SZ-h;
		int R = L+k-1;
		int rval = lseg.query(R, R).f;
		pi rang = lseg.getRang(rval);
		if(R == rang.s){
			lseg.upd(L, R, 1);
			continue;
		}
		if(rang.f <= L){
			lseg.upd(rang.s-k+1, rang.s, 1);
			continue;
		}
		int leftover = k-(rang.f-L);
		lseg.upd(rang.s-leftover+1, rang.s, 1);
		lseg.upd(L, rang.f-1, 1);
	}

	ll ans = 0;

	for(int i = SZ-mx; i < SZ; i++){
		ll val = lseg.query(i, i).f;
		ans+=((val)*(val-1))/2;
	}

	ps(ans);

	// you should actually read the stuff at the bottom
}

/* stuff you should look for
	* int overflow, array bounds
	* special cases (n=1?)
	* do smth instead of nothing and stay organized
	* WRITE STUFF DOWN
*/

Compilation message (stderr)

sails.cpp: In function 'void setIn(str)':
sails.cpp:168:28: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
  168 | void setIn(str s) { freopen(s.c_str(),"r",stdin); }
      |                     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~
sails.cpp: In function 'void setOut(str)':
sails.cpp:169:29: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
  169 | void setOut(str s) { freopen(s.c_str(),"w",stdout); }
      |                      ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 5 / 5
• Subtask 2: 10 / 10
• Subtask 3: 10 / 10
• Subtask 4: 5 / 5
• Subtask 5: 10 / 10
• Subtask 6: 10 / 10
• Subtask 7: 10 / 10
• Subtask 8: 10 / 10
• Subtask 9: 10 / 10
• Subtask 10: 10 / 10
• Subtask 11: 10 / 10