Submission #336753

#	Time	Username	Problem	Language	Result	Execution time	Memory
336753		CSQ31	Election (BOI18_election)	C++14	0 / 100	37 ms	74220 KiB

election

#pragma GCC optimize("Ofast") 
#include<bits/stdc++.h>
using namespace std;
#define pb push_back
#define fi first
#define se second
#define mp make_pair
#define all(a) a.begin(),a.end()
#define sz(a) (int)(a.size())
#define lb lower_bound
#define ub upper_bound
#define owo ios_base::sync_with_stdio(0);cin.tie(0);
#define MOD (ll)(1e9+7)
#define INF (ll)(1e18)
#define debug(...) fprintf(stderr, __VA_ARGS__),fflush(stderr)
#define time__(d) for(long blockTime = 0; (blockTime == 0 ? (blockTime=clock()) != 0 : false);\
debug("%s time : %.4fs\n", d, (double)(clock() - blockTime) / CLOCKS_PER_SEC))
typedef long long int ll;
typedef long double ld;
typedef pair<ll,ll> PII;
typedef pair<int,int> pii;
typedef vector<vector<int>> vii;
typedef vector<vector<ll>> VII;
ll gcd(ll A,ll B) {if(!B)return A;return gcd(B,A%B);}
const int MAXN = 555555;
struct node{
	ll sum=0,ans=0;
	ll pmx=-MAXN,smx=-MAXN;
};
vector<ll>s(MAXN);
node merge(node a,node b){
	node c;
	c.sum = a.sum+b.sum;
	c.pmx = max(a.pmx,a.sum+b.pmx);
	c.smx = max(b.smx,a.smx+b.sum);
	c.ans = max(a.pmx+b.smx,max(a.ans+b.sum,b.ans+a.sum));
	c.ans = max(0LL,c.ans);
	return c;
}
vector<node>t(4*MAXN);
void build(int v,int l,int r){
	//cout<<l<<" "<<r<<'\n';
	if(l == r){
		t[v].sum = t[v].smx = t[v].pmx = s[l];
		t[v].ans = s[l]==1?0:1;
		return;
	}
	int mid = (l+r)/2;
	build(2*v,l,mid);
	build(2*v+1,mid+1,r);
	t[v] = merge(t[2*v],t[2*v+1]);
}
node query(int v,int l,int r,int tl,int tr){
	if(l > r){
		node a;
		a.pmx = a.smx = 0;
		return a;
	}
	if(tl == l && r == tr)return t[v];
	int tm = (tl+tr)/2;
	node a = query(2*v,l,min(tm,r),tl,tm);
	node b = query(2*v+1,max(l,tm+1),r,tm+1,tr);
	return merge(a,b);
}
int main()
{
	owo
	int n,q;
	cin>>n;
	for(int i=1;i<=n;i++){
		char c;cin>>c;
		s[i] = c=='C'?-1:1;
	}
	build(1,1,n);
	//cout<<t[1].ans<<'\n';
	cin>>q;
	while(q--){
		int l,r;
		cin>>l>>r;
		node ans = query(1,l,r,1,n);
		cout<<ans.ans<<'\n';
	}
}

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