Submission #705068

#	Time	Username	Problem	Language	Result	Execution time	Memory
705068		Zflop	Election (BOI18_election)	C++14	28 / 100	6 ms	4744 KiB

election

#include <bits/stdc++.h>
using namespace std;

#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
 
/*
ID: 10002181
LANG: C++
TASK: lamps
*/
 
using str = string; // yay python!
using ld = long double; // or double, if TL is tight
using ll = long long;
using int64 = ll;
using db = double;
using ull = unsigned long long;
 
#define ch() getchar()
#define pc(x) putchar(x)
#define tcT template<class T
#define tcTU tcT, class U
tcT> using V = vector<T>;
tcT, size_t SZ> using AR = array<T,SZ>;
using vi = V<int>;
using vb = V<bool>;
using vpi = V<pair<int,int>>;
using vvi = V<vi>;
using vl = V<ll>;
using vd = V<ld>;
using vstr = V<str>;
 
#define all(x) begin(x), end(x)
#define sor(x) sort(all(x))
#define rev(x) reverse(all(x))
#define sz(x) (int)(x).size()
#define rall(x) x.rbegin(), x.rend()
#define AR array
 
// loops
#define F0R(i, a, b) for (int i=a; i<b;++i)
#define FOR(i, a) for (int i=0; i<a;++i)
#define FORn(i, a) for (int i=1; i<=a;++i)
#define ROF(i,a) for(int i=a-1; i >= 0;--i)
#define R0F(i,a,b) for(int i=a; i > b;--i)
#define ROFn(i,a) for(int i=a; i > 0;--i)
#define rep(a) F0R(_, a)
#define trav(i,x) for(auto& i:x)
 
// pairs
#define mp make_pair
#define pi pair <int, int>
#define f first
#define s second
 
// vectors
#define lb lower_bound
#define ub upper_bound
#define SUM(v) accumulate(all(v), 0LL)
#define MN(v) *min_element(all(v))
#define MX(v) *max_element(all(v))
#define UNIQUE(a) (a).erase(unique((a).begin(),(a).end()),(a).end())
#define eb emplace_back
#define ft front()
#define bk back()
#define ins insert
#define pf push_front
#define pb push_back
#define emt empty()
#define rsz resize
 
#define pob pop_back()
#define pof pop_front()
 
#define swp(a,b) a^=b^=a^=b
 
#define ts to_string
 
#define setIO()  ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL)
 
const ll MOD = 1e9+7;
const ll MAX = 100000000000;
const ll INF = 1e18; // not too close to LLONG_MAX
const ld PI = acos((ld)-1);
 
#ifdef _DEBUG
    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);
#endif
 
const int dx[4] = {1,0,-1,0}, dy[4] = {0,1,0,-1}; // for every grid problem!!
 
tcT> bool ckmin(T& a, const T& b) {
	return b < a ? a = b, 1 : 0; } // set a = min(a,b)
tcT> bool ckmax(T& a, const T& b) {
	return a < b ? a = b, 1 : 0; }
 
tcTU> T fstTrue(T lo, T hi, U f) {
	hi ++; assert(lo <= hi); // assuming f is increasing
	while (lo < hi) { // find first index such that f is true
		T mid = lo+(hi-lo)/2;
		f(mid) ? hi = mid : lo = mid+1;
	}
	return lo;
}
tcTU> T lstTrue(T lo, T hi, U f) {
	lo --; assert(lo <= hi); // assuming f is decreasing
	while (lo < hi) { // find first index such that f is true
		T mid = lo+(hi-lo+1)/2;
		f(mid) ? lo = mid : hi = mid-1;
	}
	return lo;
}
 
//INPUT
#define tcTUU tcT, class ...U
tcT> void re(complex<T>& c);
tcTU> void re(pair<T,U>& p);
tcT> void re(V<T>& v);
tcT, size_t SZ> void re(AR<T,SZ>& a);
 
tcT> void re(T& x) { cin >> x; }
void re(db& d) { str t; re(t); d = stod(t); }
void re(ld& d) { str t; re(t); d = stold(t); }
tcTUU> void re(T& t, U&... u) { re(t); re(u...); }
 
tcT> void re(complex<T>& c) { T a,b; re(a,b); c = {a,b}; }
tcTU> void re(pair<T,U>& p) { re(p.f,p.s); }
tcT> void re(V<T>& x) { trav(a,x) re(a); }
tcT> void rv(int n, V<T>& x) { x.rsz(n); re(x); }
 
//OUTPUT
namespace output {
	tcT> void PS(V<T>& x) { FOR(i,sz(x)) cout << x[i] << " \n"[i + 1 == sz(x)];}
	tcT> void PS(bool ok) { if(ok) cout << "YES\n"; else cout << "NO\n"; }
    template<class T1, class T2> void pr(const pair<T1,T2>& x);
    tcT, size_t SZ> void pr(const array<T,SZ>& x);
    tcT> void pr(const vector<T>& x);
    tcT> void pr(const set<T>& x);
    template<class T1, class T2> void pr(const map<T1,T2>& x);
 
    tcT> void pr(const T& x) { cout << x; }
    template<class Arg, class... Args> void pr(const Arg& first, const Args&... rest) {
        pr(first); pr(rest...);
    }
 
    template<class T1, class T2> void pr(const pair<T1,T2>& x) {
        pr("{",x.f,", ",x.s,"}");
    }
    tcT> void prContain(const T& x) {
        pr("{");
        bool fst = 1; trav(a,x) pr(!fst?", ":"",a), fst = 0;
        pr("}");
    }
    tcT, size_t SZ> void pr(const array<T,SZ>& x) { prContain(x); }
    tcT> void pr(const vector<T>& x) { prContain(x); }
    tcT> void pr(const set<T>& x) { prContain(x); }
    template<class T1, class T2> void pr(const map<T1,T2>& x) { prContain(x); }
 
    void ps() { pr("\n"); } // print w/ spaces
    template<class Arg> void ps(const Arg& first) { pr(first,"\n"); }
    template<class Arg, class... Args> void ps(const Arg& first, const Args&... rest) {
        pr(first," "); ps(rest...);
    }
}
 
using namespace output;
 
template <int MOD_> struct modnum {
	static constexpr int MOD = MOD_;
	static_assert(MOD_ > 0, "MOD must be positive");
 
private:
	using ll = long long;
 
	int v;
 
	static int minv(int a, int m) {
		a %= m;
		assert(a);
		return a == 1 ? 1 : int(m - ll(minv(m, a)) * ll(m) / a);
	}
 
public:
 
	modnum() : v(0) {}
	modnum(ll v_) : v(int(v_ % MOD)) { if (v < 0) v += MOD; }
	explicit operator int() const { return v; }
	friend std::ostream& operator << (std::ostream& out, const modnum& n) { return out << int(n); }
	friend std::istream& operator >> (std::istream& in, modnum& n) { ll v_; in >> v_; n = modnum(v_); return in; }
 
	friend bool operator == (const modnum& a, const modnum& b) { return a.v == b.v; }
	friend bool operator != (const modnum& a, const modnum& b) { return a.v != b.v; }
 
	modnum inv() const {
		modnum res;
		res.v = minv(v, MOD);
		return res;
	}
	friend modnum inv(const modnum& m) { return m.inv(); }
	modnum neg() const {
		modnum res;
		res.v = v ? MOD-v : 0;
		return res;
	}
	friend modnum neg(const modnum& m) { return m.neg(); }
 
	modnum operator- () const {
		return neg();
	}
	modnum operator+ () const {
		return modnum(*this);
	}
 
	modnum& operator ++ () {
		v ++;
		if (v == MOD) v = 0;
		return *this;
	}
	modnum& operator -- () {
		if (v == 0) v = MOD;
		v --;
		return *this;
	}
	modnum& operator += (const modnum& o) {
		v += o.v;
		if (v >= MOD) v -= MOD;
		return *this;
	}
	modnum& operator -= (const modnum& o) {
		v -= o.v;
		if (v < 0) v += MOD;
		return *this;
	}
	modnum& operator *= (const modnum& o) {
		v = int(ll(v) * ll(o.v) % MOD);
		return *this;
	}
	modnum& operator /= (const modnum& o) {
		return *this *= o.inv();
	}
 
	friend modnum operator ++ (modnum& a, int) { modnum r = a; ++a; return r; }
	friend modnum operator -- (modnum& a, int) { modnum r = a; --a; return r; }
	friend modnum operator + (const modnum& a, const modnum& b) { return modnum(a) += b; }
	friend modnum operator - (const modnum& a, const modnum& b) { return modnum(a) -= b; }
	friend modnum operator * (const modnum& a, const modnum& b) { return modnum(a) *= b; }
	friend modnum operator / (const modnum& a, const modnum& b) { return modnum(a) /= b; }
};
 
void setF(string fileName = "") {
	ios_base::sync_with_stdio(0); cin.tie(0);
	if((int)fileName.size()) {
		freopen((fileName+".in").c_str(), "r", stdin);
		freopen((fileName+".out").c_str(), "w", stdout);
	}
}
 
vi SIEVE(int N){ // sieve in O(N)
	vi pr;
	vb b(N);
	vi g(N);
	F0R(i,2,N){
		if(!b[i]){
			pr.pb(i);
			for (int j = i + i; j < N; j += i) b[j] = true;
			}
		}
	return pr;
	}
 
struct DSU {
	vector<int> e;
	DSU(int N) { e = vector<int>(N, -1); }
 
	int get(int x) { return e[x] < 0 ? x : e[x] = get(e[x]); }
 
	bool same_set(int a, int b) { return get(a) == get(b); }
 
	int size(int x) { return -e[get(x)]; }
 
	bool unite(int x, int y) {  // union by size
		x = get(x), y = get(y);
		if (x == y) return false;
		if (e[x] > e[y]) swap(x, y);
		e[x] += e[y]; e[y] = x;
		return true;
	}
};

template<class T> using ordset = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;

struct edge{
	int a;
	int b;
	int w;
	};
 
ll POW(ll x, ll y,ll mod = INF){
    ll res = 1LL;
    x %= mod;
    while(y){
        if (y & 1LL)
            res *= x;
        res %= mod;
        x = (x*x) % mod;
        y >>= 1LL;
    }
    return res;
}
 
ll gauss(ll n) { return n * (n + 1ll) / 2; }
 
ll fact(ll x) { if(x) return x * fact(x - 1ll); return 1; }
 
vl fc;
void F(int N,ll MOD){
	fc.rsz(N + 1);
	fc[0] = 1;
	FORn(i,N) fc[i] = fc[i - 1] * i * 1ll % MOD;
	}
	
vl inv;
void I(int N,ll MOD){
	inv.rsz(N + 1);
	inv[N] = POW(fc[N],MOD - 2,MOD);
	for (int i = N; i ;--i) inv[i - 1] = inv[i] * 1ll * i % MOD;
	}
 
ll Cr(ll N,ll K,ll mod){
	if(K < 0) return 0;
	if(K > N) return 0;
	return fc[N] * 1ll * inv[K] % mod * inv[N - K] % mod;
	}
ll iv(int k,ll MOD){
  return POW(k,MOD-2,MOD);  
}
/*
 scanf("%lld", &testInteger);
 printf("%lld", testInteger);
 
 ____ ____ ____ ____ ____  ____
||f |||l |||o |||p |||p ||||y ||
||__|||__|||__|||__|||__||||__||
|/__\|/__\|/__\|/__\|/__\||/__\|
 
**/
int N;
vi A;
const int NMAX = (int)1e5;
struct Node{
		int mxp,mxs,val,ans;
		Node operator+(Node b){
			Node ret;
			ret.mxp = max(mxp,val + b.mxp);
			ret.mxs = max(b.mxs,b.val + mxs);
			ret.val = val + b.val;
			ret.ans = max({val + b.ans,ans + b.val,mxp + b.mxs});
			return ret;
			}
		};
int give(char a){
	return (a == 'T' ? 1 : -1);
	}
template <class T> class SEG {
	 private:
		int n;
	public:
		Node c[NMAX];
		void init(int N) { n = 4 * N; memset(c,0,sizeof c); }
		void build(int l,int r,int x){
			if(l == r){
				if(A[l] == 1) c[x] = {1,1,1,1};
				else c[x] = {0,0,-1,0};
				return;
				}
			int mid = (l + r) / 2;
			build(l,mid,2 * x);
			build(mid + 1,r,2 * x + 1);
			c[x] = c[2 * x] + c[2 * x + 1];
			}
		void build(){
			build(1,N,1);
			}
		Node query(int a,int b,int l,int r,int x){
			if(a <= l && r <= b) return c[x];
			if(a > r || b < l) return {0,0,0,0};
			int mid = (l + r) / 2;
			return query(a,b,l,mid,2 * x) + query(a,b,mid + 1,r,2 * x + 1); 
			}
		Node query(int l,int r){
			return query(l,r,1,N,1);
			}
	};
template <class T> class BIT { // 1 indexed
  private:
	int n;
	vector<T> c;
	vector<T> a;

  public:
	BIT(int N) : n(N),c(N + 1),a(N + 1){};
	
	T sum(int i){
		if(i <= 0 || i > n) return 0;
		return c[i] + sum(i - (i & -i));
		}
	
	void add(int i,int v){
		if(i > n || i <= 0) return;
		for (int k = i; k <= n; k += (k & -k)) c[k] += v;
		}
	
	};
void solve() {
	cin >> N;
	str S; cin >> S;
	A.rsz(N + 1);
	FORn(i,N) A[i] = give(S[i - 1]);
	int Q; cin >> Q;
	SEG<ll>C;
	C.init(N);
	C.build();
	while(Q--){
		int l,r; cin >> l >> r;
		cout << C.query(l,r).ans << '\n';
		}
	
}
main()
{   setIO();
	solve();
}
// look out for out of bounds arrays
// And more importantly, is y a vowel? Damian:1
// <3 :L ._. <_<
// You have no idea how high I can fly
	

Compilation message (stderr)

election.cpp:431:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
  431 | main()
      | ^~~~
election.cpp: In function 'void setF(std::string)':
election.cpp:255:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  255 |   freopen((fileName+".in").c_str(), "r", stdin);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
election.cpp:256:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  256 |   freopen((fileName+".out").c_str(), "w", stdout);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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