Submission #942677

#	Time	Username	Problem	Language	Result	Execution time	Memory
942677		thunopro	Sum Zero (RMI20_sumzero)	C++14	100 / 100	907 ms	16164 KiB

sumzero

#include<bits/stdc++.h>
using namespace std ; 
#define maxn 400009 
#define ll long long 
#define fi first 
#define se second 
#define pb push_back 
#define left id<<1
#define right id<<1|1 
#define re exit(0); 
#define _lower(x) lower_bound(v.begin(),v.end(),x)-v.begin()
#define TIME 1.0*clock()/CLOCKS_PER_SEC

const int mod = 1e9+7; 
const int INF = 1e9; 

typedef vector<int> vi; 
typedef pair<int,int> pii;
typedef vector<pii> vii;  
typedef vector<ll> vl;

void add ( int &a , int b ) 
{
	a += b ; 
	if ( a > mod ) a -= mod ; 
	if ( a < 0 ) a += mod ; 
}

template <typename T> void chkmin ( T &a , T b ) { if ( a > b ) a = b ; }
template <typename T> void chkmax ( T &a , T b ) { if ( a < b ) a = b ; }

int _pow ( int a , int n ) 
{
	if ( n == 0 ) return 1 ;
	int res = _pow (a,n/2) ; 
	if ( n % 2 ) return 1ll*res*res%mod*a%mod ; 
	else return 1ll*res*res%mod ; 
}

void rf () 
{
	freopen ("bai1.inp","r",stdin) ;
}

const int LOG = 2 ; 
int n , nq ; 
int a [maxn] ; 

int L [maxn][3] ; 

const int B = 7 ; 

void build () 
{
	ll sum = 0 ; 
	unordered_map <ll,int> mp ; 
	mp [0] = n+1 ; 
	memset ( L , 0x3f , sizeof L ) ; 
	for ( int i = n ; i >= 1 ; i -- ) 
	{
		sum += a [i] ; 
		if ( mp [sum] ) L [i][0] = mp [sum] - 1 ; 
		chkmin (L[i][0],L[i+1][0]) ; 
		mp [sum] = i ;
	}
	for ( int j = 1 ; j <= LOG ; j ++ ) 
	{
		for ( int i = 1 ; i <= n ; i ++ ) 
		{
			if ( L[i][j-1] <= n ) L [i][j] = L [i][j-1] ; 
			else
			{
				L [i][j] = INF ; 
				continue ; 
			}
			for ( int t = 1 ; t < (1<<B) ; t ++ )
			{
				if ( L [i][j] <= n ) L [i][j] = L [L[i][j]+1][j-1] ; 
				else 
				{
					L [i][j] = INF ; break ; 
				}
			}
		}
	}
}
int main () 
{
	ios_base::sync_with_stdio(0); 
	cin.tie(0);cout.tie(0);
//	rf () ; 
	
	cin >> n ; 
	for ( int i = 1 ; i <= n ; i ++ ) cin >> a [i] ; 
	
	build () ; 
	
	cin >> nq ; 
	while ( nq -- ) 
	{
		int l , r ; cin >> l >> r ;
		int res = 0 ; 
		for ( int j = LOG ; j >= 0 ; j -- ) 
		{
			while ( L [l][j] <= r ) 
			{
				res += 1<<(B*j) ; 
				l = L [l][j]+1 ; 
			}
		}
		cout << res << "\n" ; 
	}
}

Compilation message (stderr)

sumzero.cpp: In function 'void rf()':
sumzero.cpp:42:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   42 |  freopen ("bai1.inp","r",stdin) ;
      |  ~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~

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