Submission #891559

#	Time	Username	Problem	Language	Result	Execution time	Memory
891559		fanwen	Sum Zero (RMI20_sumzero)	C++17	0 / 100	8 ms	31324 KiB

sumzero

#include <bits/stdc++.h>

using namespace std;

#define fi first
#define se second
#define ll long long
#define file(name)                  \
    if(fopen(name".inp", "r"))      \
        freopen(name".inp", "r", stdin), freopen(name".out", "w", stdout);

const int MAX = 4e5 + 5;

int n, a[MAX], q, f[19][MAX];
map <long long, int> dd;

void you_make_it(void) {
    long long pref = 0;
    cin >> n;
    memset(f, -1, sizeof f);
    dd[0] = 0;
    for (int i = 1; i <= n; ++i) {
        cin >> a[i];
        pref += a[i];
        if(dd.count(pref)) f[0][i] = dd[pref];
        f[0][i] = max(f[0][i - 1], f[0][i]);
        dd[pref] = i;
    //    cout << f[0][i] << " \n"[i == n];
    }
    for (int i = 1; i < 19; ++i) {
        for (int u = 1; u <= n; ++u) f[i][u] = (f[i - 1][u] == -1 ? -1 : f[i - 1][f[i - 1][u]]);
    }

    cin >> q; while(q--) {
        int l, r; cin >> l >> r;
        int ans = 0;
        for (int i = 19 - 1; i >= 0; --i) if(r >= l - 1 && f[i][r] >= l - 1) {
            ans |= (1 << i);
            r = f[i][r];
        }
        cout << ans << '\n';
    }
}

signed main() {

#ifdef LOCAL
    freopen("TASK.inp", "r", stdin);
    freopen("TASK.out", "w", stdout);
#endif
    file("sum0");
    auto start_time = chrono::steady_clock::now();

    cin.tie(0), cout.tie(0) -> sync_with_stdio(0);

    you_make_it();

    auto end_time = chrono::steady_clock::now();

    cerr << "\nExecution time : " << chrono::duration_cast <chrono::milliseconds> (end_time - start_time).count() << "[ms]" << endl;

    return (0 ^ 0);
}

// Dream it. Wish it. Do it.

Compilation message (stderr)

sumzero.cpp: In function 'int main()':
sumzero.cpp:10:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   10 |         freopen(name".inp", "r", stdin), freopen(name".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
sumzero.cpp:51:5: note: in expansion of macro 'file'
   51 |     file("sum0");
      |     ^~~~
sumzero.cpp:10:49: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   10 |         freopen(name".inp", "r", stdin), freopen(name".out", "w", stdout);
      |                                          ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
sumzero.cpp:51:5: note: in expansion of macro 'file'
   51 |     file("sum0");
      |     ^~~~

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