Submission #537862

#	Time	Username	Problem	Language	Result	Execution time	Memory
537862		vladislav11	Sum Zero (RMI20_sumzero)	C++14	61 / 100	113 ms	16744 KiB

sumzero

#include <bits/stdc++.h>

using namespace std;

using ll = long long;

int n;
vector<ll> a;
vector<ll> nxt;
vector< pair<int,int> > jmp;

int main ()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);

    cin >> n;

    a.assign( n+1, 0 );
    for ( int i=1; i<=n; i++ )
        cin >> a[i];

    for ( int i=1; i<=n; i++ )
        a[i] += a[i-1];

    nxt.assign( n+1, -1 );

    map<ll,int> seen;

    for ( int i=n; i>=0; i-- )
    {
        if ( seen.count(a[i]) )
            nxt[i+1] = seen[ a[i] ];

        seen[ a[i] ] = i;
    }

    a.clear();
    seen.clear();

    if ( n >= 400000 )
        return 0;

    for ( int i=n-1; i>=0; i-- )
    {
        if ( nxt[i] == -1 )
            nxt[i] = nxt[i+1];
        else if ( nxt[i+1] != -1 )
            nxt[i] = min( nxt[i], nxt[i+1] );
    }

    jmp.assign( n+1, {-1,-1} );

    for ( int i=n; i>=0; i-- )
    if ( nxt[i] != -1 )
    {
        if ( nxt[i] == n )
            jmp[i] = { 1, n };
        else if ( jmp[ nxt[i]+1 ].first != -1 )
        {
            if ( jmp[ nxt[i]+1 ].second+1 <= n )
            {
                if ( jmp[ jmp[ nxt[i]+1 ].second+1 ].first == jmp[ nxt[i]+1 ].first )
                    jmp[i] = { 1+2*jmp[ nxt[i]+1 ].first, jmp[ jmp[ nxt[i]+1 ].second+1 ].second };
                else
                    jmp[i] = { 1, nxt[i] };
            }
            else
                jmp[i] = { 1, nxt[i] };
        }
        else
            jmp[i] = { 1, n };
    }

    int q;
    cin >> q;
    while ( q-- )
    {
        int l, r;
        cin >> l >> r;

        int ans = 0;

        while ( l <= r && jmp[l].second != -1 )
        {
            if ( jmp[l].second <= r )
            {
                ans += jmp[l].first;
                l = jmp[l].second+1;
            }
            else if ( nxt[l] <= r )
            {
                ans++;
                l = nxt[l]+1;
            }
            else
                break;

            //cout << ": " << l << '\n';
        }

        cout << ans << '\n';
    }

    return 0;
}

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