Submission #402267

#	Time	Username	Problem	Language	Result	Execution time	Memory
402267		nandonathaniel	Sum Zero (RMI20_sumzero)	C++14	61 / 100	595 ms	25452 KiB

sumzero

#include<bits/stdc++.h>
using namespace std;
const int MAXN=400001,LOG=4;
int kiri[MAXN],pa[LOG][MAXN];
unordered_map<long long,int> idx;
 
int main(){
	ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);
	int N,Q,L,R,A;
	cin >> N;
	memset(kiri,-1,sizeof(kiri));
	long long pref=0;
	idx[0]=0;
	for(int i=1;i<=N;i++){
		cin >> A;
		pref+=A;
		if(idx.count(pref))kiri[i]=idx[pref];
		idx[pref]=i;
	}
	for(int i=N;i>=0;i--){
		//find j minimum st j>i and kiri[j]>=i
		if(i==N)pa[0][i]=N+1;
		else{
			if(pa[0][i])pa[0][i]=min(pa[0][i+1],pa[0][i]);
			else pa[0][i]=pa[0][i+1];
		}
		for(int j=1;j<LOG;j++){
			pa[j][i]=pa[j-1][pa[j-1][pa[j-1][pa[j-1][pa[j-1][pa[j-1][pa[j-1][pa[j-1][pa[j-1][pa[j-1][pa[j-1][pa[j-1][pa[j-1][pa[j-1][pa[j-1][pa[j-1][pa[j-1][pa[j-1][pa[j-1][pa[j-1][pa[j-1][pa[j-1][pa[j-1][pa[j-1][pa[j-1][pa[j-1][pa[j-1][i]]]]]]]]]]]]]]]]]]]]]]]]]]];
			if(pa[j][i]==0)pa[j][i]=N+1;
		}
		if(kiri[i]!=-1)pa[0][kiri[i]]=i;
	}
	cin >> Q;
	while(Q--){
		cin >> L >> R;
		int ans=0,now=pa[0][L-1];
		if(now>R){
			cout << 0 << '\n';
			continue;
		}
		int pkt=1;
		for(int i=1;i<=LOG-1;i++)pkt*=27;
		for(int i=LOG-1;i>=0;i--){
			for(int j=0;j<27;j++){
				if(pa[i][now]<=R){
					ans+=pkt;
					now=pa[i][now];
				}
			}
			pkt/=27;
		}
		cout << ans+1 << '\n';
	}
	return 0;
}

• Subtask 1: 22 / 22
• Subtask 2: 39 / 39
• Subtask 3: 0 / 39