Submission #475549

#	Time	Username	Problem	Language	Result	Execution time	Memory
475549		thiago_bastos	Street Lamps (APIO19_street_lamps)	C++17	20 / 100	202 ms	12168 KiB

street_lamps

#include "bits/stdc++.h"

using namespace std;

using i64 = long long;
using u64 = unsigned long long;
using i32 = int;
using u32 = unsigned;
using i16 = short;
using u16 = unsigned short;
using ld = long double;
using ii = pair<int, int>;

template<class T>
struct BIT {
	vector<T> bit;
	
	BIT(int n) {
		bit.assign(n + 1, 0);
	}
	
	void upd(int k, T x) {
		for(++k; k < int(bit.size()); k += k & -k) bit[k] += x;
	}
	
	T query(int k) {
		T ans {};
		for(++k; k > 0; k -= k & -k) ans += bit[k];
		return ans;
	}
	
	T query(int l, int r) {
		if(l > r) return (T)0;
		return query(r) - query(l - 1);
	}
};

template<class T>
struct SegTree {
	vector<T> st;
	int n;
	
	SegTree(int n) : n {n} {
		st.assign(2 * n + 1, 0);
	}
	
	void upd(int k, T x) {
		k += n;
		st[k] = x;
		for(k /= 2; k > 0; k /= 2) st[k] = max(st[2 * k], st[2 * k + 1]);
	}
	
	T query(int l, int r) {
		T ans {};
		for(l += n, r += n; l <= r; l /= 2, r /= 2) {
			if(l & 1) ans = max(ans, st[l++]);
			if(~r & 1) ans = max(ans, st[r--]);
		}
		return ans;
	}
};

void solve() {
	int n, q;
	string s;
	
	cin >> n >> q >> s;
	
	BIT<int> bit(n);
	SegTree<int> st(n);
	
	for(int i = 0; i < n; ++i) bit.upd(i, s[i] - '0');
	
	for(int i = 1; i <= q; ++i) {
		string type;
		int l, r;
		cin >> type >> l;
		--l;
		if(type == "toggle") {
			int x = s[l] - '0';
			bit.upd(l, (x ^ 1) - x);
			st.upd(l, i);
			s[l] ^= 1;
		} else {
			cin >> r;
			r -= 2;
			if(bit.query(l, r) == r - l + 1) cout << i - st.query(l, r) << '\n';
			else cout << "0\n";
		}
	}
}

int main() {
	ios_base :: sync_with_stdio(false);
	cin.tie(0);
	int t = 1;
	//cin >> t;
	while(t--) solve();
 	return 0;
}

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