Submission #552706

#	Time	Username	Problem	Language	Result	Execution time	Memory
552706		Zanite	Street Lamps (APIO19_street_lamps)	C++17	40 / 100	5078 ms	263300 KiB

street_lamps

// "I assure you that you guys won't make it to the top 4"
// - Tzaph, 21 December 2021

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

#define ll long long
#define ld long double
#define si short int
#define i8 __int128
#define pii pair<int, int>
#define pll pair<ll, ll>
#define pld pair<ld, ld>
#define psi pair<si, si>
#define pi8 pair<i8, i8>
#define pq priority_queue
#define fi first
#define se second

#define sqr(x) ((x)*(x))
#define pow2(x) (1ll << (x))
#define debug(x) cout << #x << " = " << (x) << '\n'
#define debugV(x, a) cout << #x << "[" << (a) << "] = " << (x[a]) << '\n'

#define yume using
#define wo namespace
#define kanaeyo std
#define nazotte __gnu_pbds

yume wo kanaeyo;
yume wo nazotte;

template<typename T>
using ordered_set = tree<T, null_type, less<T>, rb_tree_tag,tree_order_statistics_node_update>;

template<typename T> void chmin(T &a, T b) {a = min(a, b);}
template<typename T> void chmax(T &a, T b) {a = max(a, b);}
 
template<typename T> void maddto(T &a, T b, T mod) {a += b; a %= mod;}
template<typename T> void msubto(T &a, T b, T mod) {a -= b; while (a < 0) a += mod; a %= mod;}
template<typename T> void mmulto(T &a, T b, T mod) {a *= b; a %= mod;}
 
template<typename T> T madd(T a, T b, T mod) {a += b; a %= mod; return a;}
template<typename T> T msub(T a, T b, T mod) {a -= b; while (a < 0) a += mod; return a;}
template<typename T> T mmul(T a, T b, T mod) {a *= b; a %= mod; return a;}

const ll ModA = 998244353;
const ll ModC = 1e9 + 7;
const ll INF = 1e18;
const ll iINF = 1e9;

const ld EPS = 1e-9;
const ld iEPS = 1e-6;

const int maxN = 3e5 + 5;

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

inline pll add(pll a, pll b) {
	return {a.fi + b.fi, a.se + b.se};
}

struct Treap {
	struct Node {
		pll val, sum;
		int prior, pos, mn, mx;
		Node *left, *right;

		Node(int _pos, pll _val) {
			pos = mn = mx = _pos;
			val = sum = _val;
			prior = rng();
			left = right = nullptr;
		}
		
		void update() {
			sum = val;
			if (left) {sum = add(sum, left->sum);}
			if (right) {sum = add(sum, right->sum);}

			mn = (left ? left->mn : pos);
			mx = (right ? right->mx : pos);
		}
	};

	Node *root;

	Treap() : root(nullptr) {}

	void split(Node *T, Node *&L, Node *&R, int sep) {
		// splits T into L = [mn..pos] and R = [pos+1..mx]
		if (!T) {
			L = R = nullptr;
			return;
		}

		if (T->pos <= sep) {
			split(T->right, T->right, R, sep);
			L = T;
		} else {
			split(T->left, L, T->left, sep);
			R = T;
		}

		T->update();
	}

	void merge(Node *&T, Node *L, Node *R) {
		// merges L and R into T, assuming that all elements in L < R
		if (!L || !R) {
			T = (L ? L : R);
			return;
		}

		if (L->prior >= R->prior) {
			merge(L->right, L->right, R);
			T = L;
		} else {
			merge(R->left, L, R->left);
			T = R;
		}

		T->update();
	}

	bool find(int pos) {
		// returns TRUE if the node with position pos is present in the treap
		Node *cur = root;
		while (cur) {
			if (cur->pos == pos) {return true;}
			if (cur->pos < pos) {cur = cur->right;}
			else {cur = cur->left;}
		}
		return false;
	}

	void updateNode(Node *cur, int pos, pll val) {
		// updates node at position pos with val, assuming the node exists
		if (cur->pos == pos) {
			cur->val.fi += val.fi;
			cur->val.se += val.se;
			cur->update();
			return;
		}
		
		if (cur->pos < pos) {
			updateNode(cur->right, pos, val);
		} else {
			updateNode(cur->left, pos, val);
		}
		cur->update();
	}

	void update(int pos, pll val) {
		// if the node exists, update it
		if (find(pos)) {updateNode(root, pos, val);}
		else {
			// insert a new node
			Node *tmp = new Node(pos, val);
			Node *t1, *t2;
			split(root, t1, t2, pos);
			merge(root, t1, tmp);
			merge(root, root, t2);
		}
	}

	pll query(Node *T, int L, int R) {
		// returns sum of all nodes in the range [L..R] under node T
		if (!T) return {0, 0};
		if (T->mx < L || R < T->mn) return {0, 0};
		if (L <= T->mn && T->mx <= R) return T->sum;

		pll ret = (L <= T->pos && T->pos <= R) ? (T->val) : make_pair(0ll, 0ll);
		if (T->left) {ret = add(ret, query(T->left, L, R));}
		if (T->right) {ret = add(ret, query(T->right, L, R));}
		return ret;
	}

	pll query(int L, int R) {
		// returns sum of all nodes in the range [L..R]
		return query(root, L, R);
	}

	void print(Node *T) {
		if (!T) return;
		printf("%d | {%lld, %lld}\n", T->pos, T->val.fi, T->val.se);
		print(T->left);
		print(T->right);
	}

	void print() {
		print(root);
	}
};

struct DynamicSegtreeBBST {
	struct Node {
		Treap inner;
		Node* left;
		Node* right;

		Node() {
			inner = Treap();
			left = right = nullptr;
		}
	};

	Node* root;
	int dim1, dim2;

	DynamicSegtreeBBST(int _dim1, int _dim2) {
		root = new Node();
		dim1 = _dim1, dim2 = _dim2;
	}

	void update(Node* cur, int l, int r, int d1, int d2, pll upd) {
		cur->inner.update(d2, upd);
		if (l == r) {return;}

		int m = (l + r) >> 1;
		if (d1 <= m) {
			if (!cur->left) {cur->left = new Node();}
			update(cur->left, l, m, d1, d2, upd);
		} else {
			if (!cur->right) {cur->right = new Node();}
			update(cur->right, m+1, r, d1, d2, upd);
		}
	}

	pll query(Node* cur, int l, int r, int d1l, int d1r, int d2l, int d2r) {
		if (l > d1r || d1l > r) {return {0, 0};}
		if (d1l <= l && r <= d1r) {
			return cur->inner.query(d2l, d2r);
		}

		int m = (l + r) >> 1;
		pll ret = {0, 0};
		if (cur->left) {ret = add(ret, query(cur->left, l, m, d1l, d1r, d2l, d2r));}
		if (cur->right) {ret = add(ret, query(cur->right, m+1, r, d1l, d1r, d2l, d2r));}
		return ret;
	}

	void print(Node* cur, ll l, ll r) {
		if (!cur) return;
		if (l == r) {
			debug(l);
			cur->inner.print();
			return;
		}

		ll m = (l + r) >> 1;
		print(cur->left, l, m);
		print(cur->right, m+1, r);
	}

	void print() {
		print(root, 1, dim1);
	}
};

struct PairTreap {
	struct Node {
		pll val;
		int prior;
		Node *left, *right;

		Node(pll _val) {
			val = _val;
			prior = rng();
			left = right = nullptr;
		}
	};

	Node *root;

	PairTreap() : root(nullptr) {}

	void split(Node *T, Node *&L, Node *&R, ll sep) {
		// splits T into L = [mn..sep] and R = [sep+1..mx]
		if (!T) {
			L = R = nullptr;
			return;
		}

		if (T->val.fi <= sep) {
			split(T->right, T->right, R, sep);
			L = T;
		} else {
			split(T->left, L, T->left, sep);
			R = T;
		}
	}

	void merge(Node *&T, Node *L, Node *R) {
		// merges L and R into T, assuming that all elements in L < R
		if (!L || !R) {
			T = (L ? L : R);
			return;
		}

		if (L->prior >= R->prior) {
			merge(L->right, L->right, R);
			T = L;
		} else {
			merge(R->left, L, R->left);
			T = R;
		}
	}

	pll find(Node *cur, int x) {
		// returns the largest node in the treap whose first element is <= x
		if (cur->val.fi <= x) {
			pll ret = cur->val;
			if (cur->right) {ret = max(ret, find(cur->right, x));}
			return ret;
		} else {
			if (cur->left) return find(cur->left, x);
			else return {-1, -1};
		}
	}

	pll find(int x) {
		return find(root, x);
	}

	void insert(pll val) {
		// insert a new node
		Node *tmp = new Node(val);
		Node *t1, *t2;
		split(root, t1, t2, val.fi);
		merge(root, t1, tmp);
		merge(root, root, t2);
	}

	void erase(pll val) {
		Node *t1, *t2, *t3, *t4;
		split(root, t1, t2, val.fi);
		split(t1, t3, t4, val.fi - 1);
		merge(root, t3, t2);
	}

	void print(Node* cur) {
		if (!cur) return;
		print(cur->left);
		cout << cur->val.fi << ' ' << cur->val.se << '\n';
		print(cur->right);
	}

	void print() {
		print(root);
	}
};

int n, q;
bool lamps[maxN];

int main() {
	scanf("%d %d", &n, &q);

	char c;
	for (int i = 1; i <= n; i++) {
		scanf(" %c", &c);
		lamps[i] = (c == '1');
	}

	DynamicSegtreeBBST D = DynamicSegtreeBBST(n, n);
	PairTreap segments = PairTreap();

	for (int start = -1, i = 1; i <= n+1; i++) {
		if (lamps[i]) {
			if (start == -1) {start = i;}
		} else {
			if (start != -1) {
				segments.insert({start, (i-1)});
				D.update(D.root, 1, n, start, i-1, {q, 1});
				start = -1;
			}
		}
	}
	//segments.print();

	char typ[10];
	for (int a, b, i = 1; i <= q; i++) {
		scanf(" %s", typ);
		if (typ[0] == 't') {
			scanf("%d", &a);
			if (lamps[a]) {
				// toggle the lamp off

				// remove segment of current lamp
				pll cseg = segments.find(a);
				//cout << "cseg " << cseg.fi << ' ' << cseg.se << '\n';
				D.update(D.root, 1, n, cseg.fi, cseg.se, {-(q-i), -1});
				segments.erase(cseg);

				// insert new segments (except if it's of length 0)

				// left segment
				if (a != cseg.fi) {
					segments.insert({cseg.fi, (a-1)});
					D.update(D.root, 1, n, cseg.fi, a-1, {q-i, 1});
				}
				// right segment
				if (a != cseg.se) {
					segments.insert({(a+1), cseg.se});
					D.update(D.root, 1, n, a+1, cseg.se, {q-i, 1});
				}

			} else {
				// toggle the lamp on
				pll newseg = {a, a};

				// check if lamps next to it are on

				// left
				if (lamps[a-1]) {
					pll lseg = segments.find(a-1);
					D.update(D.root, 1, n, lseg.fi, lseg.se, {-(q-i), -1});
					newseg.fi = lseg.fi;
					segments.erase(lseg);
				}
				// right
				if (lamps[a+1]) {
					pll rseg = segments.find(a+1);
					D.update(D.root, 1, n, rseg.fi, rseg.se, {-(q-i), -1});
					newseg.se = rseg.se;
					segments.erase(rseg);
				}

				// insert new segment
				segments.insert(newseg);
				D.update(D.root, 1, n, newseg.fi, newseg.se, {q-i, 1});
			}

			lamps[a] = !lamps[a];

		} else {
			scanf("%d %d", &a, &b);

			pll ans = D.query(D.root, 1, n, 1, a, b-1, n);
			//cout << ans.fi << ' ' << ans.se << '\n';
			ll fin = ans.fi - (1ll * ans.se * (q-i));
			printf("%lld\n", fin);
		}

		/*
		debug(i);
		segments.print();

		//for (auto i : segments) {cout << "{" << i.fi << ", " << i.se << "} ";}
		cout << '\n';
		D.print();
		cout << '\n';
		*/
	}
}

Compilation message (stderr)

street_lamps.cpp: In function 'int main()':
street_lamps.cpp:359:7: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
  359 |  scanf("%d %d", &n, &q);
      |  ~~~~~^~~~~~~~~~~~~~~~~
street_lamps.cpp:363:8: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
  363 |   scanf(" %c", &c);
      |   ~~~~~^~~~~~~~~~~
street_lamps.cpp:385:8: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
  385 |   scanf(" %s", typ);
      |   ~~~~~^~~~~~~~~~~~
street_lamps.cpp:387:9: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
  387 |    scanf("%d", &a);
      |    ~~~~~^~~~~~~~~~
street_lamps.cpp:439:9: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
  439 |    scanf("%d %d", &a, &b);
      |    ~~~~~^~~~~~~~~~~~~~~~~

• Subtask 1: 20 / 20
• Subtask 2: 20 / 20
• Subtask 3: 0 / 20
• Subtask 4: 0 / 20
• Subtask 5: 0 / 20