Submission #1235156

#	Time	Username	Problem	Language	Result	Execution time	Memory
1235156		CodeLakVN	Vudu (COCI15_vudu)	C++20	140 / 140	227 ms	24324 KiB

vudu

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

#define task "main"
#define no "NO"
#define yes "YES"
#define F first
#define S second
#define vec vector
#define _mp make_pair
#define ii pair<int, int>
#define sz(x) (int)x.size()
#define all(x) x.begin(), x.end()
#define evoid(val) return void(std::cout << val)
#define FOR(i, a, b) for(int i = (a); i <= (b); ++i)
#define FOD(i, b, a) for(int i = (b); i >= (a); --i)

const int MAX_N = (int)1e6 + 6;

int n, p;
int a[MAX_N];

int bit[MAX_N];

void update(int idx, int val) {
    for (; idx <= MAX_N - 2; idx += (idx & -idx))
        bit[idx] += val;
}

int get(int idx) {
    int res = 0;
    for (; idx > 0; idx -= (idx & -idx))   
        res += bit[idx];
    return res;
}

void solve() {
    cin >> n;
    FOR(i, 1, n) cin >> a[i];
    cin >> p;

    memset(bit, 0, sizeof(bit));
    vector<long long> sum(n + 1, 0);
    vector<long long> com;
    FOR(i, 1, n) {
        a[i] -= p;
        sum[i] = sum[i - 1] + 1LL * a[i];
        com.push_back(sum[i]);
    }
    com.push_back(0);
    sort(com.begin(), com.end());
    com.erase(unique(com.begin(), com.end()), com.end());
    long long ans = 0;
    update(lower_bound(com.begin(), com.end(), 0) - com.begin() + 1, 1);
    FOR(i, 1, n) {
        sum[i] = lower_bound(com.begin(), com.end(), sum[i]) - com.begin() + 1;
        ans += 1LL * get(sum[i]);
        update(sum[i], 1);
    }

    cout << ans << "\n";
}

int32_t main() {
    if (fopen(task".inp", "r")) {
        freopen(task".inp", "r", stdin);
        freopen(task".out", "w", stdout);
    }
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);

    bool multitest = 0;
    int numTest = 1;
    if (multitest) cin >> numTest;

    while (numTest--) {
        solve();
    }

    return 0;
}

/* Lak lu theo dieu nhac!!!! */

Compilation message (stderr)

vudu.cpp: In function 'int32_t main()':
vudu.cpp:66:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   66 |         freopen(task".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
vudu.cpp:67:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   67 |         freopen(task".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 140 / 140