Submission #907378

#	Time	Username	Problem	Language	Result	Execution time	Memory
907378		Mathias	Election (BOI18_election)	C++14	0 / 100	4 ms	7000 KiB

election

#include <bits/stdc++.h>
using namespace std;
const int BASE = 1<<19;
const int INF = 1e9+7;
int d1[2*BASE], d2[2*BASE], suf[BASE], pref[BASE], t[BASE];
int mini1(int x,int y){
	x+=BASE-1, y+=BASE+1; int r=INF;
	while(x/2 != y/2){
		if(x%2==0) r=min(r,d1[x+1]);
		if(y%2==1) r=min(r,d1[y-1]);
		x/=2; y/=2;
	}
	return r;
}
int mini2(int x,int y){
	x+=BASE-1, y+=BASE+1; int r=INF;
	while(x/2 != y/2){
		if(x%2==0) r=min(r,d2[x+1]);
		if(y%2==1) r=min(r,d2[y-1]);
		x/=2; y/=2;
	}
	return r;
}
int main(){
	ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
	int n,a,b,q,r1,r2;
	char c;
	cin>>n;
	for(int i=1;i<=n;i++){
		cin>>c;
		if(c=='T') t[i]=-1;
		else t[i]=1;
		pref[i]=pref[i-1]+t[i];
	}
	for(int i=n;i>=1;i--) suf[i]=suf[i+1]+t[i];
	for(int i=1;i<=n;i++) d1[i+BASE]=pref[i];
	for(int i=1;i<=n;i++) d2[i+BASE]=suf[i];
	for(int i=BASE-1;i>=1;i--){
		d1[i]=min(d1[2*i], d1[2*i+1]);
		d2[i]=min(d2[2*i], d2[2*i+1]);
	}	
	cin>>q;
	while(q--){
		cin>>a>>b;
		r1=mini1(a,b)-pref[a-1];
		r2=mini2(a,b)-suf[b+1];
		if(min(r1,r2)<0) cout<<-min(r1,r2)<<'\n';
		else cout<<0<<'\n';
	}
	return 0;
}

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