Submission #942745

#	Time	Username	Problem	Language	Result	Execution time	Memory
942745		ShadowShark	Sum Zero (RMI20_sumzero)	C++17	61 / 100	721 ms	32180 KiB

sumzero

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

const int maxN = 4e5 + 9;
int *a;
int jump[9][maxN];
map<long long, int> appear;
vector<pair<int, int>> segment;

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

    int n;
    cin >> n;

    a = new int[n + 1];

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

    appear[0] = 0;
    long long sum = 0;

    for (int i = 1; i <= n; i++) {
        sum = sum + a[i];
        if (appear[sum] != 0)
            segment.push_back({i, appear[sum] + 1});
        else if (sum == 0)
            segment.push_back({i, 1});
        appear[sum] = i;
    }

    appear.clear();
    delete[] a;

    sort(segment.begin(), segment.end());

    int curr = 0;
    jump[0][n + 1] = n + 1;
    for (int i = 0; i <= n; i++) {
        while (curr < segment.size() && i >= segment[curr].second) curr++;

        if (curr == segment.size()) jump[0][i] = n + 1;
            else jump[0][i] = segment[curr].first;
    }

    for (int i = 1; i <= 8; i++)
        for (int j = 0; j <= n + 1; j++)
            jump[i][j] = jump[i - 1][jump[i - 1][j]];

    int q;
    cin >> q;
    while (q--) {
        int l, r;
        cin >> l >> r;
        int ans = 0; l--;
        for (int i = 8; i >= 0; i--)
            while (jump[i][l] <= r) {
                l = jump[i][l];
                ans += 1 << i;
            }
        cout << ans << '\n';
    }

    return 0;
}

Compilation message (stderr)

sumzero.cpp: In function 'int main()':
sumzero.cpp:41:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   41 |         while (curr < segment.size() && i >= segment[curr].second) curr++;
      |                ~~~~~^~~~~~~~~~~~~~~~
sumzero.cpp:43:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   43 |         if (curr == segment.size()) jump[0][i] = n + 1;
      |             ~~~~~^~~~~~~~~~~~~~~~~

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