답안 #59347

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
59347 2018-07-21T15:39:53 Z Benq Vudu (COCI15_vudu) C++11
140 / 140
420 ms 21948 KB
#include <bits/stdc++.h>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/pb_ds/assoc_container.hpp>

using namespace std;
using namespace __gnu_pbds;
 
typedef long long ll;
typedef long double ld;
typedef complex<ld> cd;

typedef pair<int, int> pi;
typedef pair<ll,ll> pl;
typedef pair<ld,ld> pd;

typedef vector<int> vi;
typedef vector<ld> vd;
typedef vector<ll> vl;
typedef vector<pi> vpi;
typedef vector<pl> vpl;
typedef vector<cd> vcd;

template <class T> using Tree = tree<T, null_type, less<T>, rb_tree_tag,tree_order_statistics_node_update>;

#define FOR(i, a, b) for (int i=a; i<(b); i++)
#define F0R(i, a) for (int i=0; i<(a); i++)
#define FORd(i,a,b) for (int i = (b)-1; i >= a; i--)
#define F0Rd(i,a) for (int i = (a)-1; i >= 0; i--)

#define sz(x) (int)(x).size()
#define mp make_pair
#define pb push_back
#define f first
#define s second
#define lb lower_bound
#define ub upper_bound
#define all(x) x.begin(), x.end()

const int MOD = 1000000007;
const ll INF = 1e18;
const int MX = 100001;


template<class T, int SZ> struct BIT {
    T bit[SZ+1];
    
    BIT() { memset(bit,0,sizeof bit); }
    
    void upd(int k, T val) { // add val to index k
        for( ;k <= SZ; k += (k&-k)) bit[k] += val;
    }
    
    T query(int k) {
        T temp = 0;
        for (;k > 0;k -= (k&-k)) temp += bit[k];
        return temp;
    }
    T query(int l, int r) { return query(r)-query(l-1); } // range query [l,r]
};

BIT<int,1000001> B;
int N, P, v[1000001];
ll a[1000001],ans;

int main() {
    ios_base::sync_with_stdio(0); cin.tie(0);
    cin >> N;
    FOR(i,1,N+1) cin >> a[i];
    cin >> P;
    FOR(i,1,N+1) a[i] += a[i-1]-P;
    
    FOR(i,1,N+1) v[i] = i;
    sort(v,v+N+1,[](int x, int y) { if (a[x] != a[y]) return a[x] < a[y]; return x < y; } );
    F0Rd(i,N+1) {
        ans += B.query(N+1)-B.query(v[i]);
        B.upd(v[i]+1,1);
    }
    cout << ans;
}

/* Look for:
* the exact constraints (multiple sets are too slow for n=10^6 :( ) 
* special cases (n=1?)
* overflow (ll vs int?)
* array bounds
*/
# 결과 실행 시간 메모리 Grader output
1 Correct 9 ms 4344 KB Output is correct
2 Correct 8 ms 4488 KB Output is correct
3 Correct 9 ms 4488 KB Output is correct
4 Correct 413 ms 21668 KB Output is correct
5 Correct 216 ms 21668 KB Output is correct
6 Correct 351 ms 21668 KB Output is correct
7 Correct 413 ms 21668 KB Output is correct
8 Correct 311 ms 21668 KB Output is correct
9 Correct 406 ms 21948 KB Output is correct
10 Correct 420 ms 21948 KB Output is correct