Submission #999985

#	Time	Username	Problem	Language	Result	Execution time	Memory
999985		Whisper	Sum Zero (RMI20_sumzero)	C++17	61 / 100	334 ms	21060 KiB

sumzero

#include <bits/stdc++.h>

using namespace std;
using ll = long long;

//#define int long long
#define FOR(i, a, b) for (int i = (a); i <= (b); i++)
#define FORD(i, a, b) for (int i = (b); i >= (a); i --)
#define REP(i, n) for (int i = 0; i < (n); ++i)
#define REPD(i, n) for (int i = (n) - 1; i >= 0; --i)

#define MASK(i) (1LL << (i))
#define BIT(x, i) (((x) >> (i)) & 1)


constexpr ll LINF = (1ll << 60);
constexpr int INF = (1ll << 30);
constexpr int Mod = 1e9 + 7;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

/*
    Phu Trong from Nguyen Tat Thanh High School for gifted student
*/

template <class X, class Y>
    bool minimize(X &x, const Y &y){
        X eps = 1e-9;
        if (x > y + eps) {x = y; return 1;}
        return 0;
    }

template <class X, class Y>
    bool maximize(X &x, const Y &y){
        X eps = 1e-9;
        if (x + eps < y) {x = y; return 1;}
        return 0;
    }
#define MAX     400005
#define LOG     5
int nArr, numQuery;
int A[MAX];
void init(void){
    cin >> nArr;
    for (int i = 1; i <= nArr; ++i) cin >> A[i];
    cin >> numQuery;
}
struct custom_hash{
    size_t operator ()(uint64_t x) const{
        static const uint64_t FIXED_RANDOM = chrono::steady_clock::now().time_since_epoch().count();
        x ^= FIXED_RANDOM;
        return x ^ (x >> 16);
    }
};

#define All(x...) (x).begin(), (x).end()
int up[MAX][LOG];
void process(void){
    vector<pair<int, int>> segment;
    int sum = 0;
    unordered_map<int, int, custom_hash> last;
    last[0] = 0;
    for (int i = 1; i <= nArr; ++i){
        sum += A[i];
        if (last.count(sum)){
            segment.emplace_back(last[sum] + 1, i);
        }
        last[sum] = i;
    }
    sort(All(segment));

    vector<pair<int, int>> candidate;
    for (pair<int, int>& x : segment){
        while ((int)candidate.size() && candidate.back().second >= x.second) candidate.pop_back();
        candidate.push_back(x);
    }

    segment = move(candidate);
    int j = 1, N = (int)segment.size();
    for (int i = 1; i <= N; ++i){
        while (j <= N && segment[i - 1].second >= segment[j - 1].first)
            ++j;
        up[i][0] = (j > N ? 0 : j);
    }
    for (int i = 1; i < LOG; ++i){
        for (int u = 1; u <= N; ++u){
            int v = u;
            REP(j, 16) v = up[v][i - 1];
            up[u][i] = v;
        }
    }
    for (int i = 1; i <= numQuery; ++i){
        int l, r; cin >> l >> r;
        int u = lower_bound(All(segment), make_pair(l, l)) - segment.begin();
        if (u >= N || segment[u].second > r) {
            cout << "0\n"; continue;
        }
        ++u;
        int ans = 0;
        int k = LOG - 1;
        while (k >= 0){
            if (up[u][k] > 0 && segment[up[u][k] - 1].second <= r){
                u = up[u][k];
                ans += MASK(k * 4);
            }
            else{
                k--;
            }
        }
        cout << ans + 1 << '\n';
    }
}
signed main(){
    #define name "Whisper"
    cin.tie(nullptr) -> sync_with_stdio(false);
    //freopen(name".inp", "r", stdin);
    //freopen(name".out", "w", stdout);
    init();
    process();
}

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