#include <bits/stdc++.h>
// cut here
#ifdef _MSC_VER
#include <intrin.h>
#endif
namespace atcoder {
namespace internal {
int ceil_pow2(int n) {
int x = 0;
while ((1U << x) < (unsigned int)(n)) x++;
return x;
}
int bsf(unsigned int n) {
#ifdef _MSC_VER
unsigned long index;
_BitScanForward(&index, n);
return index;
#else
return __builtin_ctz(n);
#endif
}
} // namespace internal
} // namespace atcoder
namespace atcoder {
template <class S, S (*op)(S, S), S (*e)()> struct segtree {
public:
segtree() : segtree(0) {}
segtree(int n) : segtree(std::vector<S>(n, e())) {}
segtree(const std::vector<S>& v) : _n(int(v.size())) {
log = internal::ceil_pow2(_n);
size = 1 << log;
d = std::vector<S>(2 * size, e());
for (int i = 0; i < _n; i++) d[size + i] = v[i];
for (int i = size - 1; i >= 1; i--) {
update(i);
}
}
void set(int p, S x) {
assert(0 <= p && p < _n);
p += size;
d[p] = x;
for (int i = 1; i <= log; i++) update(p >> i);
}
S get(int p) {
assert(0 <= p && p < _n);
return d[p + size];
}
S prod(int l, int r) {
assert(0 <= l && l <= r && r <= _n);
S sml = e(), smr = e();
l += size;
r += size;
while (l < r) {
if (l & 1) sml = op(sml, d[l++]);
if (r & 1) smr = op(d[--r], smr);
l >>= 1;
r >>= 1;
}
return op(sml, smr);
}
S all_prod() { return d[1]; }
template <bool (*f)(S)> int max_right(int l) {
return max_right(l, [](S x) { return f(x); });
}
template <class F> int max_right(int l, F f) {
assert(0 <= l && l <= _n);
assert(f(e()));
if (l == _n) return _n;
l += size;
S sm = e();
do {
while (l % 2 == 0) l >>= 1;
if (!f(op(sm, d[l]))) {
while (l < size) {
l = (2 * l);
if (f(op(sm, d[l]))) {
sm = op(sm, d[l]);
l++;
}
}
return l - size;
}
sm = op(sm, d[l]);
l++;
} while ((l & -l) != l);
return _n;
}
template <bool (*f)(S)> int min_left(int r) {
return min_left(r, [](S x) { return f(x); });
}
template <class F> int min_left(int r, F f) {
assert(0 <= r && r <= _n);
assert(f(e()));
if (r == 0) return 0;
r += size;
S sm = e();
do {
r--;
while (r > 1 && (r % 2)) r >>= 1;
if (!f(op(d[r], sm))) {
while (r < size) {
r = (2 * r + 1);
if (f(op(d[r], sm))) {
sm = op(d[r], sm);
r--;
}
}
return r + 1 - size;
}
sm = op(d[r], sm);
} while ((r & -r) != r);
return 0;
}
private:
int _n, size, log;
std::vector<S> d;
void update(int k) { d[k] = op(d[2 * k], d[2 * k + 1]); }
};
} // namespace atcoder
// cut here
#define int ll
using namespace std;
#define rep(i,n) for(int i=0;i<n;i++)
#define rng(i,c,n) for(int i=(c);i<n;i++)
#define per(i,n) for(int i=n-1;i>=0;i--)
#define fi first
#define se second
#define pb push_back
#define sz(a) (int)a.size()
#define vec(...) vector<__VA_ARGS__>
#define _3aFGabX ios::sync_with_stdio(0),cin.tie(0)
typedef long long ll;
using pii=pair<int,int>;
using vi=vector<int>;
void print(){cout<<'\n';}
template<class h,class...t>
void print(const h&v,const t&...u){cout<<v<<' ',print(u...);}
// e
int op(int l,int r){return l+r;}
int e(){return 0;}
signed main(){
_3aFGabX;
int n;
cin>>n;
vi a(n);
rep(i,n){
cin>>a[i];
}
int pvt;
cin>>pvt;
vi ps={0};
rep(i,n){
int v=a[i]-pvt;
ps.pb(ps.back()+v);
}
vi tmp=ps;
sort(tmp.begin(), tmp.end());
tmp.erase(unique(tmp.begin(), tmp.end()),tmp.end());
const int si_tmp=sz(tmp);
atcoder::segtree<int,op,e> seg(si_tmp);
seg.set((int)(lower_bound(tmp.begin(), tmp.end(),0)-tmp.begin()),1);
int ans=0;
rng(i,1,n+1){
int v=(int)(lower_bound(tmp.begin(), tmp.end(),ps[i])-tmp.begin());
// print(ps[i]);
ans+=seg.prod(0,v+1);
seg.set(v,seg.get(v)+1);
}
print(ans);
}
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
3 ms |
596 KB |
Output is correct |
| 2 |
Correct |
2 ms |
596 KB |
Output is correct |
| 3 |
Correct |
2 ms |
596 KB |
Output is correct |
| 4 |
Correct |
414 ms |
47024 KB |
Output is correct |
| 5 |
Correct |
198 ms |
33900 KB |
Output is correct |
| 6 |
Correct |
344 ms |
51892 KB |
Output is correct |
| 7 |
Correct |
323 ms |
44628 KB |
Output is correct |
| 8 |
Correct |
317 ms |
41024 KB |
Output is correct |
| 9 |
Correct |
375 ms |
48052 KB |
Output is correct |
| 10 |
Correct |
331 ms |
43940 KB |
Output is correct |
