Submission #669998

#	Time	Username	Problem	Language	Result	Execution time	Memory
669998		ghostwriter	Election (BOI18_election)	C++17	0 / 100	4 ms	340 KiB

election

#include <bits/stdc++.h>
using namespace std;
#ifdef LOCAL
#include <debug.h>
#else
#define debug(...)
#endif
#define ft front
#define bk back
#define st first
#define nd second
#define ins insert
#define ers erase
#define pb push_back
#define pf push_front
#define _pb pop_back
#define _pf pop_front
#define lb lower_bound
#define ub upper_bound
#define mtp make_tuple
#define bg begin
#define ed end
#define all(x) (x).bg(), (x).ed()
#define sz(x) (int)(x).size()
typedef long long ll; typedef unsigned long long ull;
typedef double db; typedef long double ldb;
typedef pair<int, int> pi; typedef pair<ll, ll> pll;
typedef vector<int> vi; typedef vector<ll> vll; typedef vector<pi> vpi; typedef vector<pll> vpll;
typedef string str;
#define FOR(i, l, r) for (int i = (l); i <= (r); ++i)
#define FOS(i, r, l) for (int i = (r); i >= (l); --i)
#define FRN(i, n) for (int i = 0; i < (n); ++i)
#define FSN(i, n) for (int i = (n) - 1; i >= 0; --i)
#define EACH(i, x) for (auto &i : (x))
#define WHILE while
template<typename T> T gcd(T a, T b) { WHILE(b) { a = a % b; swap(a, b); } return a; }
template<typename T> T lcm(T a, T b) { return a / gcd(a, b) * b; }
#define file "TEST"
mt19937 rd(chrono::steady_clock::now().time_since_epoch().count());
ll rand(ll l, ll r) { return uniform_int_distribution<ll>(l, r)(rd); }
/*
----------------------------------------------------------------
    END OF TEMPLATE
----------------------------------------------------------------
    Tran The Bao - ghostwriter
    Training for VOI23 gold medal
----------------------------------------------------------------
    GOAT
----------------------------------------------------------------
*/
int n, q;
str s;
#define cost(x) (x == 'C'? 1 : -1)
int solve(const str &s) {
	vi f(sz(s), 0);
	int cur = 0, minn = 0, rs = 0;
	FRN(i, sz(s)) {
		cur += cost(s[i]);
		if (cur < minn) {
			minn = cur;
			f[i] = 1;
			++rs;
		}
	}
	minn = cur = 0;
	int cnt = 0;
	FSN(i, sz(s)) {
		cnt += f[i];
		cur += cost(s[i]);
		if (cur < minn) {
			minn = cur;
			if (cnt < -cur) ++rs;
		}
	}
	return rs;
}
signed main() {
    ios_base::sync_with_stdio(0), cin.tie(0), cout.tie(0);
    // freopen(file".inp", "r", stdin);
    // freopen(file".out", "w", stdout);
    cin >> n;
    cin >> s;
    cin >> q;
    WHILE(q--) {
    	int l, r;
    	cin >> l >> r;
    	cout << solve(s.substr(l - 1, r - l + 1)) << '\n';
    }
    return 0;
}
/*
11
CCCTTTTTTCC
1
1 11
----------------------------------------------------------------
From Benq:
    stuff you should look for
        * int overflow, array bounds
        * special cases (n=1?)
        * do smth instead of nothing and stay organized
        * WRITE STUFF DOWN
        * DON'T GET STUCK ON ONE APPROACH
----------------------------------------------------------------
*/

• Subtask 1: 0 / 28
• Subtask 2: 0 / 54
• Subtask 3: 0 / 18