Submission #1201500

#	Time	Username	Problem	Language	Result	Execution time	Memory
1201500		KK_1729	Sum Zero (RMI20_sumzero)	C++17	22 / 100	129 ms	28288 KiB

sumzero

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

#define int long long
#define FOR(i,a,b) for (int i = (a); i < (b); ++i)
#define pb push_back
#define all(a) a.begin(), a.end()
#define endl "\n"

void printVector(vector<int> a){
    for (auto x: a) cout << x << " ";
    cout << endl;
}

void solve(){

    int n; cin >> n;
    vector<int> a(n+1);

    FOR(i,1,n+1) cin >> a[i];
    vector<int> prefix(n+1);
    FOR(i,1,n+1) prefix[i] = prefix[i-1]+a[i];
    // printVector(prefix);
    map<int, vector<int>> o;
    FOR(i,1,n+1){
        o[prefix[i]].pb(i);
    }
    vector<int> intervals(n+1, 1e9);
    vector<int> suffmin(n+2, 1e9);
    FOR(i,1,n+1){
        auto ind = lower_bound(all(o[prefix[i-1]]), i);
        if (ind  == o[prefix[i-1]].end()) continue;
        intervals[i] = *ind;
    }
    for (int i = n; i >= 1; i--){
        suffmin[i] = min(intervals[i], suffmin[i+1]);
    }
    int L = 20;
    vector<vector<int>> rmq(n+5, vector<int>(L, 1e9));
    FOR(i,1,n+1){
        rmq[i][0] = suffmin[i];
    }

    for (int j = 1; j < L; j++){
        for (int i = 1; i <= n; i++){
            if (rmq[i][j-1] <= n) rmq[i][j] = rmq[ rmq[i][j-1]+1 ][j-1];   
         
        }
    }
    // cout << "a" <<rmq[5][0] << endl;
    // cout << rmq[8][0] << endl;
    int q; cin >> q;
    while (q--){
        int l, r; cin >> l >> r;
        int ans = 0;
        for (int i = L-1; i >= 0; i--){
            // cout << l << endl;
            if (l > n) break;
            if (rmq[l][i] <= r){
                // cout << "a" << l << i << endl;
                ans += (1 << i);
                // cout << ans << endl;
                l = rmq[l][i]+1;
            }
        }
        cout << ans << endl;
    }
}

int32_t main(){
    ios::sync_with_stdio(false);cin.tie(nullptr);
    int t = 1;// cin >> t;
    while (t--) solve();
}

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