oj.uz

Submission #568863

# Submission time Handle Problem Language Result Execution time Memory
568863 2022-05-26T09:42:50 Z tranxuanbach Election (BOI18_election) C++17
100 / 100
 529 ms 50284 KB 
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;

#define endl '\n'
#define fi first
#define se second
#define For(i, l, r) for (auto i = (l); i < (r); i++)
#define ForE(i, l, r) for (auto i = (l); i <= (r); i++)
#define FordE(i, l, r) for (auto i = (l); i >= (r); i--)
#define Fora(v, a) for (auto v: (a))
#define bend(a) (a).begin(), (a).end()
#define isz(a) ((signed)(a).size())

using ll = long long;
using ld = long double;
using pii = pair <int, int>;
using vi = vector <int>;
using vpii = vector <pii>;
using vvi = vector <vi>;

template<class T, class F>
struct segment_tree{
	int n, size, log;
	vector<T> data;
	F TT; // monoid operation (always adjacent)
	T T_id; // monoid identity
	// O(n)
	segment_tree(int n, F TT, T T_id): segment_tree(vector<T>(n, T_id), TT, T_id){}
	// O(n)
	segment_tree(int n, T init, F TT, T T_id): segment_tree(vector<T>(n, init), TT, T_id){}
	// O(n)
	segment_tree(const vector<T> &a, F TT, T T_id): n((int)a.size()), TT(TT), T_id(T_id){ // O(n)
		log = __lg(max(n - 1, 1)) + 1, size = 1 << log;
		data = vector<T>(size << 1, T_id);
		copy(a.begin(), a.end(), data.begin() + size);
		for(auto i = size - 1; i >= 1; -- i) refresh(i);
	}
	// O(1)
	void refresh(int i){
		data[i] = TT(data[i << 1], data[i << 1 | 1]);
	}
	// O(log n)
	void set(int p, T x){
		assert(0 <= p && p < n);
		data[p += size] = x;
		for(auto i = 1; i <= log; ++ i) refresh(p >> i);
	}
	// O(log n)
	void update(int p, T x){
		assert(0 <= p && p < n);
		p += size;
		data[p] = TT(data[p], x);
		for(auto i = 1; i <= log; ++ i) refresh(p >> i);
	}
	// O(1)
	T query(int p) const{
		assert(0 <= p && p < n);
		return data[p + size];
	}
	// O(log n)
	T query(int l, int r) const{
		assert(0 <= l && l <= r && r <= n);
		T res_left = T_id, res_right = T_id;
		for(l += size, r += size; l < r; l >>= 1, r >>= 1){
			if(l & 1) res_left = TT(res_left, data[l ++]);
			if(r & 1) res_right = TT(data[-- r], res_right);
		}
		return TT(res_left, res_right);
	}
	// O(1)
	T query_all() const{
		return data[1];
	}
	// pred(sum[l, r)) is T, T, ..., T, F, F, ..., F
	// Returns max r with T
	// O(log n)
	int max_pref(int l, auto pred) const{
		assert(0 <= l && l <= n && pred(T_id));
		if(l == n) return n;
		l += size;
		T sm = T_id;
		do{
			while(~l & 1) l >>= 1;
			if(!pred(TT(sm, data[l]))){
				while(l < size){
					l = l << 1;
					if(pred(TT(sm, data[l]))) sm = TT(sm, data[l ++]);
				}
				return l - size;
			}
			sm = TT(sm, data[l ++]);
		}while((l & -l) != l);
		return n;
	}
	// pred(sum[l, r)) is F, F, ..., F, T, T, ..., T
	// Returns min l with T
	// O(log n)
	int min_suff(int r, auto pred) const{
		assert(0 <= r && r <= n && pred(T_id));
		if(r == 0) return 0;
		r += size;
		T sm = T_id;
		do{
			-- r;
			while(r > 1 && r & 1) r >>= 1;
			if(!pred(TT(data[r], sm))){
				while(r < size){
					r = r << 1 | 1;
					if(pred(TT(data[r], sm))) sm = TT(data[r --], sm);
				}
				return r + 1 - size;
			}
			sm = TT(data[r], sm);
		}while((r & -r) != r);
		return 0;
	}
	template<class output_stream>
	friend output_stream &operator<<(output_stream &out, const segment_tree<T, F> &seg){
		out << "[";
		for(auto i = 0; i < seg.n; ++ i){
			out << seg.query(i);
			if(i != seg.n - 1) out << ", ";
		}
		return out << ']';
	}
};

const int N = 5e5 + 5;

struct node_t{
    int sum, minsuf;
    
    node_t(int x = 0){
        sum = x;
        minsuf = min(0, x);
    }
};

auto merge_node_t = [](const node_t &lhs, const node_t &rhs){
    node_t ans;
    ans.sum = lhs.sum + rhs.sum;
    ans.minsuf = min(lhs.minsuf + rhs.sum, rhs.minsuf);
    return ans;
};

segment_tree seg(N, merge_node_t, node_t());

int n;
int a[N];
int q;
pii b[N];

vi vidxb[N];
int ans[N];

signed main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);
    // freopen("KEK.inp", "r", stdin);
    // freopen("KEK.out", "w", stdout);
    cin >> n;
    ForE(i, 1, n){
        char c; cin >> c;
        a[i] = (c == 'C' ? 1 : -1);
    }
    cin >> q;
    ForE(i, 1, q){
        cin >> b[i].fi >> b[i].se;
    }
    
    ForE(i, 1, q){
        vidxb[b[i].fi].emplace_back(i);
    }
    
    vi st;
    FordE(i, n, 1){
        if (a[i] < 0){
            st.emplace_back(i);
        }
        else{
            if (!st.empty()){
                int j = st.back(); st.pop_back();
                seg.set(j, node_t(-1));
            }
            seg.set(i, node_t(1));
        }
        Fora(ib, vidxb[i]){
            int j = b[ib].se;
            node_t cac = seg.query(i, j + 1);
            int cnt = isz(st) - (lower_bound(bend(st), j, [&](int lhs, int rhs){
                return lhs > rhs;
            }) - st.begin());
            ans[ib] = -cac.minsuf + cnt;
        }
    }
    ForE(i, 1, q){
        cout << ans[i] << endl;
    }
}

/*
==================================================+
INPUT:                                            |
--------------------------------------------------|

--------------------------------------------------|
==================================================+
OUTPUT:                                           |
--------------------------------------------------|

--------------------------------------------------|
==================================================+
*/

Compilation message

election.cpp:80:22: warning: use of 'auto' in parameter declaration only available with '-fconcepts-ts'
   80 |  int max_pref(int l, auto pred) const{
      |                      ^~~~
election.cpp:101:22: warning: use of 'auto' in parameter declaration only available with '-fconcepts-ts'
  101 |  int min_suff(int r, auto pred) const{
      |                      ^~~~

Subtask #1
28.0 / 28.0

# Verdict Execution time Memory Grader output
1 Correct 14 ms 20368 KB Output is correct
2 Correct 14 ms 20296 KB Output is correct
3 Correct 14 ms 20368 KB Output is correct
4 Correct 15 ms 20328 KB Output is correct
5 Correct 16 ms 20368 KB Output is correct

Subtask #2
54.0 / 54.0

# Verdict Execution time Memory Grader output
1 Correct 14 ms 20368 KB Output is correct
2 Correct 14 ms 20296 KB Output is correct
3 Correct 14 ms 20368 KB Output is correct
4 Correct 15 ms 20328 KB Output is correct
5 Correct 16 ms 20368 KB Output is correct
6 Correct 60 ms 23988 KB Output is correct
7 Correct 53 ms 23104 KB Output is correct
8 Correct 53 ms 23332 KB Output is correct
9 Correct 49 ms 23812 KB Output is correct
10 Correct 50 ms 23864 KB Output is correct
11 Correct 58 ms 24152 KB Output is correct
12 Correct 58 ms 24100 KB Output is correct
13 Correct 62 ms 24264 KB Output is correct
14 Correct 55 ms 24072 KB Output is correct
15 Correct 51 ms 24000 KB Output is correct

Subtask #3
18.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 14 ms 20368 KB Output is correct
2 Correct 14 ms 20296 KB Output is correct
3 Correct 14 ms 20368 KB Output is correct
4 Correct 15 ms 20328 KB Output is correct
5 Correct 16 ms 20368 KB Output is correct
6 Correct 60 ms 23988 KB Output is correct
7 Correct 53 ms 23104 KB Output is correct
8 Correct 53 ms 23332 KB Output is correct
9 Correct 49 ms 23812 KB Output is correct
10 Correct 50 ms 23864 KB Output is correct
11 Correct 58 ms 24152 KB Output is correct
12 Correct 58 ms 24100 KB Output is correct
13 Correct 62 ms 24264 KB Output is correct
14 Correct 55 ms 24072 KB Output is correct
15 Correct 51 ms 24000 KB Output is correct
16 Correct 529 ms 47584 KB Output is correct
17 Correct 362 ms 41360 KB Output is correct
18 Correct 354 ms 43684 KB Output is correct
19 Correct 352 ms 45944 KB Output is correct
20 Correct 450 ms 46752 KB Output is correct
21 Correct 499 ms 49376 KB Output is correct
22 Correct 454 ms 48556 KB Output is correct
23 Correct 506 ms 50284 KB Output is correct
24 Correct 438 ms 48984 KB Output is correct
25 Correct 472 ms 47904 KB Output is correct