Submission #212413

#	Time	Username	Problem	Language	Result	Execution time	Memory
212413		Benq	Constellation 3 (JOI20_constellation3)	C++14	100 / 100	780 ms	110104 KiB

constellation3

#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}; 

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 bit(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 

// 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
template<class A, class B> str ts(pair<A,B> p);
template<class A> str ts(complex<A> c) { return ts(mp(c.real(),c.imag())); }
str ts(bool b) { return b ? "true" : "false"; }
str ts(char c) { str s = ""; s += c; return s; }
str ts(str s) { return s; }
str ts(const char* s) { return (str)s; }
str ts(vector<bool> v) { 
	bool fst = 1; str res = "{";
	F0R(i,sz(v)) {
		if (!fst) res += ", ";
		fst = 0; res += ts(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 T> str ts(T v) {
	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 << to_string(h); if (sizeof...(t)) cerr << ", ";
	DBG(t...); }
#ifdef LOCAL // compile with -DLOCAL
#define dbg(...) cerr << "[" << #__VA_ARGS__ << "]: [", DBG(__VA_ARGS__)
#else
#define dbg(...) 42
#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
}

mt19937 rng((uint32_t)chrono::steady_clock::now().time_since_epoch().count()); 

/**
 * Description: 1D range minimum query. Can also do queries 
 	* for any associative operation in $O(1)$ with D\&C
 * Source: KACTL
 * Verification: 
	* https://cses.fi/problemset/stats/1647/
	* http://wcipeg.com/problem/ioi1223
	* https://pastebin.com/ChpniVZL
 * Memory: O(N\log N)
 * Time: O(1)
 */

template<class T> struct RMQ { // floor(log_2(x))
	int level(int x) { return 31-__builtin_clz(x); } 
	vector<T> v; vector<vi> jmp;
	int comb(int a, int b) { // index of min
		return v[a]==v[b]?min(a,b):(v[a]>v[b]?a:b); } 
	void init(const vector<T>& _v) {
		v = _v; jmp = {vi(sz(v))}; iota(all(jmp[0]),0);
		for (int j = 1; 1<<j <= sz(v); ++j) {
			jmp.pb(vi(sz(v)-(1<<j)+1));
			F0R(i,sz(jmp[j])) jmp[j][i] = comb(jmp[j-1][i],
									jmp[j-1][i+(1<<(j-1))]);
		}
	}
	int index(int l, int r) { // get index of min element
		int d = level(r-l+1);
		return comb(jmp[d][l],jmp[d][r-(1<<d)+1]); }
	T query(int l, int r) { return v[index(l,r)]; }
};

RMQ<int> R;
int N,M,depth[MX],par[MX][18];
vi A;
vpi path[MX];
ll dp[MX];

int lef(int X, int Y) {
	int lo = 0, hi = X-1;
	while (lo < hi) {
		int mid = (lo+hi+1)/2;
		if (R.query(mid,X-1) >= Y) lo = mid;
		else hi = mid-1;
	}
	return lo;
}

int rig(int X, int Y) {
	int lo = X+1, hi = N+1;
	while (lo < hi) {
		int mid = (lo+hi)/2;
		if (R.query(X+1,mid) >= Y) hi = mid;
		else lo = mid+1;
	}
	return lo;
}

int cat(int X, int Y) {
	int LL = lef(X,Y), RR = rig(X,Y);
	return R.index(LL+1,RR-1);
}

bool doneDp[MX][18],doneChild[MX][18];
ll sdp[MX][18],schild[MX][18],child[MX];

ll getChild(int hi, int i) {
	if (i == 0) return child[hi];
	if (doneChild[hi][i]) return schild[hi][i];
	doneChild[hi][i] = 1;
	return schild[hi][i] = getChild(hi,i-1)+getChild(par[hi][i-1],i-1);
}
ll getDp(int hi, int i) {
	if (i == 0) return dp[hi];
	if (doneDp[hi][i]) return sdp[hi][i];
	doneDp[hi][i] = 1;
	return sdp[hi][i] = getDp(hi,i-1)+getDp(par[hi][i-1],i-1);
}
ll sumChild(int hi, int d) {
	ll res = 0;
	R0F(i,18) if (d&(1<<i)) {
		res += getChild(hi,i);
		hi = par[hi][i];
	}
	return res;
}

ll sumDp(int hi, int d) {
	ll res = 0;
	R0F(i,18) if (d&(1<<i)) {
		res += getDp(hi,i);
		hi = par[hi][i];
	}
	return res;
}

ll qpath(int hi, int lo) {
	int d = depth[hi]-depth[lo]+1; assert(d >= 1);
	return sumChild(hi,d)-sumDp(hi,d-1);
}

int divi(int l, int r, int pre) {
	if (l > r) return 0;
	int x = R.index(l,r); depth[x] = depth[pre]+1;
	par[x][0] = pre; FOR(i,1,18) par[x][i] = par[par[x][i-1]][i-1];
	int L = divi(l,x-1,x), R = divi(x+1,r,x); 
	child[x] = dp[L]+dp[R]; ckmax(dp[x],child[x]);
	//dbg(x,L,R,dp[x],child[x]);
	trav(t,path[x]) ckmax(dp[x],qpath(t.f,x)+t.s);
	return x;
}

int main() {
	setIO(); re(N); A.rsz(N+2);
	A[0] = A[N+1] = N+1;
	FOR(i,1,N+1) re(A[i]);
	R.init(A);
	re(M);
	ll sum = 0;
	F0R(i,M) {
		int X,Y,C; re(X,Y,C);
		path[cat(X,Y)].pb({X,C});
		//dbg("WUT",X,Y,cat(X,Y));
		sum += C;
	}
	int x = divi(1,N,0); ps(sum-dp[x]);
	// 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)

constellation3.cpp: In function 'void setIn(std::__cxx11::string)':
constellation3.cpp:123:31: 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); }
                        ~~~~~~~^~~~~~~~~~~~~~~~~~~~~
constellation3.cpp: In function 'void setOut(std::__cxx11::string)':
constellation3.cpp:124:32: 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: 14 / 14
• Subtask 2: 21 / 21
• Subtask 3: 65 / 65