Submission #729259

#	Time	Username	Problem	Language	Result	Execution time	Memory
729259		YENGOYAN	Election (BOI18_election)	C++17	100 / 100	536 ms	27992 KiB

election

/*
                                    //\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\\
                                    \\                                    //
                                    //  271828___182845__904523__53602__  \\
                                    \\  87___47____13______52____66__24_  //
                                    //  97___75____72______47____09___36  \\
                                    \\  999595_____74______96____69___67  //
                                    //  62___77____24______07____66__30_  \\
                                    \\  35___35____47______59____45713__  //
                                    //                                    \\
                                    \\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\//
*/
#include <algorithm>
#include <bitset>
#include <chrono>
#include <climits>
#include <cmath>
#include <cstdio>
#include <ctime>
#include <deque>
#include <fstream>
#include <functional>
#include <iomanip>
#include <iostream>
#include <map>
#include <queue>
#include <random>
#include <set>
#include <stack>
#include <string>
#include <tuple>
#include <unordered_map>
#include <unordered_set>
#include <vector>
 
using namespace std;
using LL = long long;
const int N = 1e5 + 5;
const LL mod = 1e9 + 7, inf = 1e9;
 
vector<int> dx = { 1, 0, 0, -1, 1, 1, -1, -1 };
vector<int> dy = { 0, 1, -1, 0, 1, -1, 1, -1 };

int n, q;
string s;

struct node {
  int l, r, sm, a;
};

vector<node> seg;

node merge(node left, node right) {
  node cur;
  cur.l = max(left.l, left.sm + right.l);
  cur.r = max(right.r, right.sm + left.r);
  cur.sm = left.sm + right.sm;
  cur.a = max({left.a + right.sm, left.sm + right.a, left.l + right.r});
  return cur;
}

void build(int lx, int rx, int u){
  if(lx == rx) {
    if(lx < n) {
      if(s[lx] == 'T') {
        seg[u].l = seg[u].r = seg[u].sm = seg[u].a = 1;
      }
      else {
        seg[u].l = seg[u].r = 0;
        seg[u].sm = -1;
        seg[u].a = 0;
      }
    }
    else {
      seg[u].l = seg[u].r = seg[u].sm = seg[u].a = 0;
    }
    return;
  }
  int m = (lx + rx) / 2;
  build(lx, m, 2 * u + 1), build(m + 1, rx, 2 * u + 2);
  seg[u] = merge(seg[2 * u + 1], seg[2 * u + 2]);
}

node get(int ll, int rr, int lx, int rx, int u){
  if(lx >= ll && rx <= rr){
    return seg[u];
  }
  if(lx > rr || rx < ll) {
    return {0, 0, 0, 0};
  }
  int m = (lx + rx) / 2;
  return merge(get(ll, rr, lx, m, 2 * u + 1), get(ll, rr, m + 1, rx, 2 * u + 2));
}

void solve() {
  cin >> n >> s >> q;
  int sz = 1;
  while(sz < n) {
    sz <<= 1;
  }
  seg = vector<node> (2 * sz);
  build(0, sz - 1, 0);
  while(q--){
    int l, r; cin >> l >> r;
    cout << get(l - 1, r - 1, 0, sz - 1, 0).a << "\n";
  }
}

int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  // int t; cin >> t; while(t--)
    solve();
}

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