Submission #1263242

#	Time	Username	Problem	Language	Result	Execution time	Memory
1263242		duonggsimp	Sum Zero (RMI20_sumzero)	C++20	0 / 100	1101 ms	41268 KiB

sumzero

#include <bits/stdc++.h>
using namespace std;

const int MAXN = 200005;
const int LOG = 20; 

int n, q;
long long a[MAXN], pre[MAXN];
int nxt[MAXN][LOG + 1];

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    cin >> n >> q;
    for (int i = 1; i <= n; i++) cin >> a[i];

    pre[0] = 0;
    for (int i = 1; i <= n; i++) pre[i] = pre[i - 1] + a[i];

    unordered_map<long long, int> last;
    for (int i = n; i >= 0; i--) {
        if (last.count(pre[i])) nxt[i][0] = last[pre[i]];
        else nxt[i][0] = n + 1; 
        last[pre[i]] = i;
    }

    for (int j = 1; j <= LOG; j++) {
        for (int i = 0; i <= n + 1; i++) {
            int mid = nxt[i][j - 1];
            if (mid <= n) nxt[i][j] = nxt[mid][j - 1];
            else nxt[i][j] = n + 1;
        }
    }

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

        int ans = 0;
        int pos = l - 1; 
        for (int j = LOG; j >= 0; j--) {
            if (nxt[pos][j] <= r) {
                ans += (1 << j);
                pos = nxt[pos][j];
            }
        }
        cout << ans << "\n";
    }
}

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