Submission #1098273

#	Time	Username	Problem	Language	Result	Execution time	Memory
1098273		Nelt	Sum Zero (RMI20_sumzero)	C++17	61 / 100	299 ms	53248 KiB

sumzero

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#define ll long long
#define endl "\n"

using namespace std;
using namespace __gnu_pbds;

mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
template <typename T, typename key = less<T>>
using ordered_set = tree<T, null_type, key, rb_tree_tag, tree_order_statistics_node_update>;
const ll lg = 19, N = 4e5 + 5;
int up[lg][N];
void solve()
{
    int n;
    cin >> n;
    int a[n + 1];
    ll pref[n + 1];
    pref[0] = 0;
    for (int i = 1; i <= n; i++)
        cin >> a[i], pref[i] = pref[i - 1] + a[i];
    map<ll, int> last;
    int mn = n + 1;
    for (int i = n; i >= 1; i--)
    {
        last[pref[i]] = i;
        if (last.count(pref[i - 1])) mn = min(mn, last[pref[i - 1]]);
        up[0][i] = mn + 1;
    }
    // for (int i = 1; i <= n; i++) cout << up[0][i] << " \n"[i == n];
    for (int i = 0; i < lg; i++) up[i][n + 2] = up[i][n + 1] = n + 2;
    for (int bit = 1; bit < lg; bit++)
    for (int i = 1; i <= n; i++) up[bit][i] = min((int)n + 2, up[bit - 1][up[bit - 1][i]]);
    int q;
    cin >> q;
    // cout << up[18][1] << endl;
    while (q--)
    {
        int l, r;
        cin >> l >> r;
        int ans = 0;
        for (ll bit = lg - 1; bit >= 0; bit--)
            if (up[bit][l] <= r + 1) ans += 1 << bit, l = up[bit][l];
        cout << ans << endl;
    }
}

int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    ll t = 1;
    // precomp();
    // cin >> t;
    for (ll cs = 1; cs <= t; cs++)
        solve();
    // cerr << "\nTime elapsed: " << clock() * 1000.0 / CLOCKS_PER_SEC << " ms\n";
}

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