Submission #918943

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
918943	2024-01-30T21:43:18 Z	myst6	Election (BOI18_election)	C++14	100 / 100	755 ms	43844 KB

election

#include <bits/stdc++.h>
 
using namespace std;
 
struct Tree {
	vector<int> info, tags;
	Tree(int size) {
		info.resize(size*4, 0);
		tags.resize(size*4);
	}
	void pushdown(int x) {
		info[x] += tags[x];
		if (x*2 < tags.size()) tags[x*2] += tags[x];
		if (x*2+1 < tags.size()) tags[x*2+1] += tags[x];
		tags[x] = 0;
	}
	void update(int l, int r, int x, int xl, int xr, int tag) {
		if (l > r) return;
		if (l == xl && r == xr) {
			tags[x] += tag;
		} else {
			int xm = (xl+xr)/2;
			update(l, min(r,xm), x*2, xl, xm, tag);
			update(max(l,xm+1), r, x*2+1, xm+1, xr, tag);
			pushdown(x*2); pushdown(x*2+1);
			info[x] = min(info[x*2], info[x*2+1]);
		}
	}
	int query(int l, int r, int x, int xl, int xr) {
		if (l > r) return 1<<30;
		pushdown(x);
		if (l == xl && r == xr) {
			return info[x];
		} else {
			int xm = (xl+xr)/2;
			int left = query(l, min(r,xm), x*2, xl, xm);
			int right = query(max(l,xm+1), r, x*2+1, xm+1, xr);
			return min(left, right);
		}
	}
};
 
struct BIT {
	vector<int> data;
	BIT(int size) {
		data.resize(size+1);
	}
	void update(int x, int delta) {
		while (x < data.size()) {
			data[x] += delta;
			x += x & (-x);
		}
	}
	int query(int x) {
		int ans = 0;
		while (x > 0) {
			ans += data[x];
			x -= x & (-x);
		}
		return ans;
	}
};
 
int main() {
	cin.tie(0)->sync_with_stdio(0);
	int N;
	cin >> N;
	string s;
	cin >> s;
	int Q;
	cin >> Q;
	vector<pair<int,int>> queries(Q);
	for (int i=0; i<Q; i++) {
		int L, R;
		cin >> L >> R;
		queries[i] = {L-1, R-1};
	}
	vector<int> order(Q);
	iota(order.begin(), order.end(), 0);
	sort(order.begin(), order.end(), [&](int i, int j) -> bool {
		return queries[i].first > queries[j].first;
	});
	int L = N-1;
	set<int> Xs;
	BIT left(N);
	Tree right(N);
	vector<int> ans(Q);
	for (int i=0; i<Q; i++) {
		pair<int,int> q = queries[order[i]];
		while (L >= q.first) {
			if (s[L] == 'C') {
				if (!Xs.empty()) {
					int idx = *Xs.begin();
					left.update(idx+1, -1);
					right.update(0, idx, 1, 0, N-1, -1);
					Xs.erase(idx);
				}
				right.update(0, L, 1, 0, N-1, +1);
			} else {
				Xs.insert(L);
				left.update(L+1, +1);
			}
			L -= 1;
		}
		int R = q.second;
		int base = left.query(R+1);
		int extra = right.query(L+1, R, 1, 0, N-1);
		int next = R == N-1 ? 0 : right.query(R+1, R+1, 1, 0, N-1);
		ans[order[i]] = base - min(0, extra - next);
	}
	for (int i=0; i<Q; i++) {
		cout << ans[i] << "\n";
	}
	return 0;
}

Compilation message

election.cpp: In member function 'void Tree::pushdown(int)':
election.cpp:13:11: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   13 |   if (x*2 < tags.size()) tags[x*2] += tags[x];
      |       ~~~~^~~~~~~~~~~~~
election.cpp:14:13: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   14 |   if (x*2+1 < tags.size()) tags[x*2+1] += tags[x];
      |       ~~~~~~^~~~~~~~~~~~~
election.cpp: In member function 'void BIT::update(int, int)':
election.cpp:49:12: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   49 |   while (x < data.size()) {
      |          ~~^~~~~~~~~~~~~

Subtask #1

28.0 / 28.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	2 ms	360 KB	Output is correct
2	Correct	2 ms	360 KB	Output is correct
3	Correct	2 ms	348 KB	Output is correct
4	Correct	2 ms	604 KB	Output is correct
5	Correct	2 ms	600 KB	Output is correct

Subtask #2

54.0 / 54.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	2 ms	360 KB	Output is correct
2	Correct	2 ms	360 KB	Output is correct
3	Correct	2 ms	348 KB	Output is correct
4	Correct	2 ms	604 KB	Output is correct
5	Correct	2 ms	600 KB	Output is correct
6	Correct	73 ms	5408 KB	Output is correct
7	Correct	74 ms	5456 KB	Output is correct
8	Correct	69 ms	5200 KB	Output is correct
9	Correct	65 ms	5164 KB	Output is correct
10	Correct	71 ms	5152 KB	Output is correct
11	Correct	76 ms	5832 KB	Output is correct
12	Correct	73 ms	5624 KB	Output is correct
13	Correct	70 ms	6404 KB	Output is correct
14	Correct	71 ms	5616 KB	Output is correct
15	Correct	72 ms	5412 KB	Output is correct

Subtask #3

18.0 / 18.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	2 ms	360 KB	Output is correct
2	Correct	2 ms	360 KB	Output is correct
3	Correct	2 ms	348 KB	Output is correct
4	Correct	2 ms	604 KB	Output is correct
5	Correct	2 ms	600 KB	Output is correct
6	Correct	73 ms	5408 KB	Output is correct
7	Correct	74 ms	5456 KB	Output is correct
8	Correct	69 ms	5200 KB	Output is correct
9	Correct	65 ms	5164 KB	Output is correct
10	Correct	71 ms	5152 KB	Output is correct
11	Correct	76 ms	5832 KB	Output is correct
12	Correct	73 ms	5624 KB	Output is correct
13	Correct	70 ms	6404 KB	Output is correct
14	Correct	71 ms	5616 KB	Output is correct
15	Correct	72 ms	5412 KB	Output is correct
16	Correct	676 ms	36024 KB	Output is correct
17	Correct	595 ms	35544 KB	Output is correct
18	Correct	673 ms	35860 KB	Output is correct
19	Correct	607 ms	35300 KB	Output is correct
20	Correct	682 ms	35256 KB	Output is correct
21	Correct	755 ms	41744 KB	Output is correct
22	Correct	719 ms	38088 KB	Output is correct
23	Correct	701 ms	43844 KB	Output is correct
24	Correct	733 ms	39780 KB	Output is correct
25	Correct	649 ms	36836 KB	Output is correct