Submission #330874

#	Time	Username	Problem	Language	Result	Execution time	Memory
330874		Benq	Hedgehog Daniyar and Algorithms (IZhO19_sortbooks)	C++14	100 / 100	2534 ms	106992 KiB

sortbooks

#include <bits/stdc++.h>
using namespace std;
 
using ll = long long;
using ld = long double;
using db = double; 
using str = string; // yay python!

using pi = pair<int,int>;
using pl = pair<ll,ll>;
using pd = pair<db,db>;

using vi = vector<int>;
using vb = vector<bool>;
using vl = vector<ll>;
using vd = vector<db>; 
using vs = vector<str>;
using vpi = vector<pi>;
using vpl = vector<pl>; 
using vpd = vector<pd>;

#define tcT template<class T
#define tcTU tcT, class U
// ^ lol this makes everything look weird but I'll try it
tcT> using V = vector<T>; 
tcT, size_t SZ> using AR = array<T,SZ>; 
tcT> using PR = pair<T,T>;

// pairs
#define mp make_pair
#define f first
#define s second

// vectors
#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 

// loops
#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 = 1e6+5;
const ll INF = 1e18; // not too close to LLONG_MAX
const ld PI = acos((ld)-1);
const int dx[4] = {1,0,-1,0}, dy[4] = {0,1,0,-1}; // for every grid problem!!
mt19937 rng((uint32_t)chrono::steady_clock::now().time_since_epoch().count()); 
template<class T> using pqg = priority_queue<T,vector<T>,greater<T>>;

// helper funcs
constexpr int pct(int x) { return __builtin_popcount(x); } // # of bits set
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

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;
}
tcT> void remDup(vector<T>& v) { // sort and remove duplicates
	sort(all(v)); v.erase(unique(all(v)),end(v)); }
tcTU> void erase(T& t, const U& u) { // don't erase
	auto it = t.find(u); assert(it != end(t));
	t.erase(it); } // element that doesn't exist from (multi)set

// INPUT
#define tcTUU tcT, class ...U
tcT> void re(complex<T>& c);
tcTU> void re(pair<T,U>& p);
tcT> void re(vector<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(vector<T>& x) { trav(a,x) re(a); }
tcT, size_t SZ> void re(AR<T,SZ>& x) { trav(a,x) re(a); }
tcT> void rv(int& n, vector<T>& x) { re(n); x.rsz(n); 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
}
tcT> str ts(complex<T> 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; }
tcTU> str ts(pair<T,U> p);
tcT> 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
}
tcTU> str ts(pair<T,U> p) {
	#ifdef LOCAL
		return "("+ts(p.f)+", "+ts(p.s)+")"; 
	#else
		return ts(p.f)+" "+ts(p.s);
	#endif
}

// OUTPUT
tcT> void pr(T x) { cout << ts(x); }
tcTUU> void pr(const T& t, const U&... u) { 
	pr(t); pr(u...); }
void ps() { pr("\n"); } // print w/ spaces
tcTUU> void ps(const T& t, const U&... u) { 
	pr(t); if (sizeof...(u)) pr(" "); ps(u...); }

// DEBUG
void DBG() { cerr << "]" << endl; }
tcTUU> void DBG(const T& t, const U&... u) {
	cerr << ts(t); if (sizeof...(u)) cerr << ", ";
	DBG(u...); }
#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
}

int N,M, l[MX], r[MX], k[MX];
vi stor_by_left[MX];
int ans_right[MX], ans_left[MX], mx_left[MX];
vi ans;
vi W;

void go(int lo, int hi, vi todo) {
	if (lo == hi || !sz(todo)) return;
	vi lef, rig, tmp;
	int mid = (lo+hi)/2;
	trav(t,todo) {
		if (r[t] <= mid) lef.pb(t);
		else if (l[t] > mid) rig.pb(t);
		else tmp.pb(t);
	}
	vi sorted_left, sorted_right; // ties broken by index
	// do right
	// sorted left
	FOR(i,lo,mid+1) {
		ans_left[i] = 0;
		sorted_left.pb(i);
		stor_by_left[i].clear();
	}
	dbg(lo,hi,tmp);
	trav(q,tmp) stor_by_left[l[q]].pb(q);
	FOR(i,mid+1,hi+1) sorted_right.pb(i);
	auto cmp = [&](int x, int y) {
		return mp(W[x],x) < mp(W[y],y);
	};
	sort(all(sorted_left),cmp); sort(all(sorted_right),cmp);
	{
		int mx = 0, ans_so_far = 0;
		FOR(i,mid+1,hi+1) {
			ckmax(mx,W[i]);
			if (mx > W[i]) ckmax(ans_so_far,mx+W[i]);
			ans_right[i] = ans_so_far;
		}
		trav(q,tmp) ckmax(ans[q],ans_right[r[q]]);
	}
	{
		vi st;
		trav(ind,sorted_left) {
			while (sz(st) && st.bk < ind) st.pop_back();
			if (sz(st)) ckmax(ans_left[ind],W[ind]+W[st.bk]);
			st.pb(ind);
		}
	}
	FOR(i,lo,mid+1) mx_left[i] = W[i];
	ROF(i,lo,mid) {
		ckmax(ans_left[i],ans_left[i+1]);
		ckmax(mx_left[i],mx_left[i+1]);
	}
	// dbg(ans_right[4],ans_left[1]);
	{
		vi st; int rind = 0;
		ROF(ind,lo,mid+1) {
			auto ins_rig = [&](int x) {
				while (sz(st) && st.bk > x) st.pop_back();
				// dbg("ADDING",x,W[x]);
				st.pb(x);
			};
			while (rind < sz(sorted_right) && W[sorted_right[rind]] < mx_left[ind])
				ins_rig(sorted_right[rind++]);
			trav(q,stor_by_left[ind]) {
				// dbg("HA",q,mx_left[ind]);
				ckmax(ans[q],ans_left[ind]);
				auto it = ub(all(st),r[q]);
				if (it != begin(st)) {
					// dbg("???",W[*prev(it)],st);
					ckmax(ans[q],mx_left[ind]+W[*prev(it)]);
				}
			}
		}
	}
	go(lo,mid,lef);
	go(mid+1,hi,rig);
}

int main() {
	setIO(); re(N,M);
	W.rsz(N); re(W);
	F0R(i,M) {
		re(l[i],r[i],k[i]);
		-- l[i], --r[i];
	}
	ans.rsz(M); 
	vi todo(M); iota(all(todo),0); go(0,N-1,todo);
	F0R(i,M) {
		dbg(i,ans[i]);
		if (ans[i] <= k[i]) ps(1);
		else ps(0);
	}
	// 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
	* DON'T GET STUCK ON ONE APPROACH
*/

Compilation message (stderr)

sortbooks.cpp: In function 'void go(int, int, vi)':
sortbooks.cpp:180:19: warning: statement has no effect [-Wunused-value]
  180 |  #define dbg(...) 0
      |                   ^
sortbooks.cpp:219:2: note: in expansion of macro 'dbg'
  219 |  dbg(lo,hi,tmp);
      |  ^~~
sortbooks.cpp: In function 'int main()':
sortbooks.cpp:180:19: warning: statement has no effect [-Wunused-value]
  180 |  #define dbg(...) 0
      |                   ^
sortbooks.cpp:284:3: note: in expansion of macro 'dbg'
  284 |   dbg(i,ans[i]);
      |   ^~~
sortbooks.cpp: In function 'void setIn(str)':
sortbooks.cpp:185:28: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
  185 | void setIn(str s) { freopen(s.c_str(),"r",stdin); }
      |                     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~
sortbooks.cpp: In function 'void setOut(str)':
sortbooks.cpp:186:29: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
  186 | void setOut(str s) { freopen(s.c_str(),"w",stdout); }
      |                      ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 8 / 8
• Subtask 2: 9 / 9
• Subtask 3: 13 / 13
• Subtask 4: 17 / 17
• Subtask 5: 30 / 30
• Subtask 6: 23 / 23