#include "bits/stdc++.h"
using namespace std;
#define ll long long
#define forn(i,n) for(int i=0;i<n;i++)
#define all(v) v.begin(), v.end()
#define rall(v) v.rbegin(),v.rend()
#define pb push_back
#define sz(a) (int)a.size()
const int N = 5e5;
struct node{
int pref;
int suf;
int sum;
int ans;
};
node t[4 * N];
int a[N];
node merge(node a, node b){
node c;
c.sum = a.sum + b.sum;
c.pref = max(a.pref, a.sum + b.pref);
c.suf = max(b.suf, b.sum + a.suf);
c.ans = max({0, a.ans, b.ans, c.pref, c.suf});
return c;
}
void build(int i, int l, int r)
{
if(l == r){
t[i].pref = t[i].suf = max(0, a[l]);
t[i].sum = a[l];
t[i].ans = max(0, a[l]);
return;
}
int mid = l + r >> 1;
build(2 * i, l, mid);
build(2 * i + 1, mid + 1, r);
t[i] = merge(t[2 * i], t[2 * i + 1]);
}
node neutral = {0, 0, 0, 0};
node query(int i, int l, int r, int tl, int tr)
{
if(l > tr || r < tl)return neutral;
if(l >= tl && r <= tr)return t[i];
int mid = l + r >> 1;
return merge(query(2 * i, l, mid, tl, tr), query(2 * i + 1, mid + 1, r, tl, tr));
}
void solve()
{
int n, q;
string s;
cin >> n >> s >> q;
for(int i = 0;i < n;++i){
a[i] = (s[i] == 'C' ? -1 : 1);
}
build(1, 0, n - 1);
while(q--)
{
int l, r;
cin >> l >> r;
cout << query(1, 0, n - 1, l - 1, r - 1).ans << "\n";
}
}
int32_t main()
{
ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
int t = 1;
//cin >> t;
while(t--)
{
solve();
}
}
Compilation message
election.cpp: In function 'void build(int, int, int)':
election.cpp:41:17: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
41 | int mid = l + r >> 1;
| ~~^~~
election.cpp: In function 'node query(int, int, int, int, int)':
election.cpp:53:17: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
53 | int mid = l + r >> 1;
| ~~^~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
2 ms |
332 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
2 ms |
332 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
2 ms |
332 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |