Submission #254142

#	Time	Username	Problem	Language	Result	Execution time	Memory
254142		amoo_safar	Election (BOI18_election)	C++14	100 / 100	928 ms	39700 KiB

election

// Null
#include <bits/stdc++.h>

#define pb push_back
#define F first
#define S second
#define all(x) x.begin(), x.end()
#define debug(x) cerr << #x << " : " << x << '\n'

using namespace std;

typedef long long ll;
typedef long double ld;
typedef string str;
typedef pair<ll, ll> pll;

const ll Mod = 1000000007LL;
const int N = 5e5 + 10;
const ll Inf = 2242545357980376863LL;
const ll Log = 30;

int n, q, ps[N];
str s;
int lz[N << 2], seg[N << 2];

void Apply(int id, int x){
	seg[id] += x;
	lz[id] += x;
}
void Shift(int id){
	Apply(id << 1, lz[id]);
	Apply(id << 1 | 1, lz[id]);
	lz[id] = 0;
}
void Add(int id, int l, int r, int x, int L, int R){
	if(r <= L || R <= l) return ;
	if(l <= L && R <= r){
		Apply(id, x);
		return ;
	}
	Shift(id);
	int mid = (L + R) >> 1;
	Add(id << 1, l, r, x, L, mid);
	Add(id << 1 | 1, l, r, x, mid, R);
	seg[id] = min(seg[id << 1], seg[id << 1 | 1]);
}
int Get(int id, int l, int r, int L, int R){
	if(r <= L || R <= l) return 1e9;
	if(l <= L && R <= r) return seg[id];
	Shift(id);
	int mid = (L + R) >> 1;
	return min( Get(id << 1, l, r, L, mid), Get(id << 1 | 1, l, r, mid, R) );
}

int ans[N];
vector< pair<int, int> > Q[N], M;

int main(){
	ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
	cin >> n >> s >> q;
	int l, r;
	for(int i = 0; i < q; i++){
		cin >> l >> r;
		Q[l - 1].pb({r, i});
	}
	for(int i = 1; i <= n; i++) ps[i] = ps[i - 1] + (s[i - 1] == 'T' ? 1 : -1);
	
	//for(int i = 0; i <= n; i++) cerr << ps[i] << ' ';
	//cerr << "\n\n";

	int Sm, X, Y;
	for(int i = n; i >= 0; i--){
		//Add(1, i, i + 1, ps[i], 0, n + 1);
		int la = i;
		while(!M.empty()){
			if(M.back().F > ps[i]) break;
			Add(1, la + 1, M.back().S + 1, M.back().F - ps[i], 0, n + 1);
			la = M.back().S;
			M.pop_back();
		}
		M.pb({ps[i], la});

		for(auto [r, qn] : Q[i]){
			Sm = ps[r] - ps[i];
			//debug(Get(1, r, r + 1, 0, n + 1));
			X = ps[r] - Get(1, r, r + 1, 0, n + 1) - ps[i];
			Y = (Sm - X) - Get(1, i, r + 1, 0, n + 1);

			ans[qn] = X + Y;
			//cerr << i + 1 << ' ' << r << " -> "<< Sm << ' ' << X << '\n';
		}
	}

	for(int i = 0; i < q; i++) cout << ans[i] << '\n';
	return 0;
}

Compilation message (stderr)

election.cpp: In function 'int main()':
election.cpp:83:12: warning: decomposition declaration only available with -std=c++1z or -std=gnu++1z
   for(auto [r, qn] : Q[i]){
            ^

• Subtask 1: 28 / 28
• Subtask 2: 54 / 54
• Subtask 3: 18 / 18