Submission #1311296

#	Time	Username	Problem	Language	Result	Execution time	Memory
1311296		nikaa123	Election (BOI18_election)	C++20	82 / 100	54 ms	30884 KiB

election

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

#define int long long
#define eb emplace_back
#define mp make_pair
#define pb push_back
#define pp pop_back
#define endl '\n'
#define ff first
#define ss second
#define stop exit(0)
#define sz(x) (int)x.size()
#define pause system("pause")
#define all(x) (x).begin(), (x).end()
#define deb(x) cout << #x << "-" << x << endl
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
 
typedef string str;
typedef long long ll;
typedef vector<int> vii;
typedef pair<int, int> pii;
 
const long long INF = LLONG_MAX;
const int inf = INT_MAX;
const int mod = 998244353;
const int MOD = 1000000007;
const int dx[] = {-1,0,1,0};
const int dy[] = {0,1,0,-1};
const double PI = 2 * acos(0.0);
 
const int N = 2e5+5;

int n;
string c;
map <int, int> id;
set<int> s;
int a[N];
int pref[N],suf[N],preft[N];

struct NODE{
    int sum = 0; int pref = 0;
    int suf = 0;
    int ans = 0;
} t[4*N];

NODE merge(NODE a, NODE b) {
    NODE res;
    res.sum = a.sum + b.sum;
    res.pref =max(a.pref, a.sum + b.pref);
    res.suf = max(a.suf + b.sum,b.suf);
    res.ans = max(max(a.ans+b.sum,b.ans+a.sum),a.pref+b.suf);
    return res;
}

void build(int node, int l, int r) {
    if (l == r) {
        if (c[l-1] == 'T') {
            t[node] = {1,1,1,1};
        } else {
            t[node] = {-1,0,0,0};
        }
        return;
    }
    int mid = (l+r)/2;
    build(node*2,l,mid);
    build(node*2+1,mid+1,r);
    t[node] = merge(t[node*2],t[node*2+1]);
}

NODE getans(int node, int l, int r, int L, int R) {
    if (r < L || l > R) return {0,0,0,0};
    if (l >= L && r <= R) return t[node];
    int mid = (l+r)/2;
    return merge(getans(node*2,l,mid,L,R), getans(node*2+1,mid+1,r,L,R));
}


inline void test_case() {

    cin >> n;
    cin >> c;

    build(1,1,n);
    int q;
    cin >> q;
    while (q--) {
        int l; int r;
        cin >> l >> r;
        cout << getans(1,1,n,l,r).ans << endl;
                
    }
    


}
 
signed main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
 
    int T = 1;
    // cin >> T;
    while (T--) test_case();
    return 0;
}

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