結果
| 問題 |
No.1300 Sum of Inversions
|
| コンテスト | |
| ユーザー |
 mel02
|
| 提出日時 | 2020-11-27 22:06:59 |
| 言語 | C++14 (gcc 13.3.0 + boost 1.87.0) |
| 結果 |
AC
|
| 実行時間 | 310 ms / 2,000 ms |
| コード長 | 6,136 bytes |
| コンパイル時間 | 1,906 ms |
| コンパイル使用メモリ | 180,916 KB |
| 実行使用メモリ | 32,384 KB |
| 最終ジャッジ日時 | 2024-07-26 12:56:07 |
| 合計ジャッジ時間 | 10,302 ms |
|
ジャッジサーバーID （参考情報） |
judge2 / judge4 |
（要ログイン）
| ファイルパターン | 結果 |
|---|---|
| sample | AC * 3 |
| other | AC * 34 |
ソースコード
#include <bits/stdc++.h>
#include <cassert>
#include <numeric>
#include <type_traits>
namespace atcoder {
namespace internal {
#ifndef _MSC_VER
template <class T>
using is_signed_int128 =
typename std::conditional<std::is_same<T, __int128_t>::value ||
std::is_same<T, __int128>::value,
std::true_type,
std::false_type>::type;
template <class T>
using is_unsigned_int128 =
typename std::conditional<std::is_same<T, __uint128_t>::value ||
std::is_same<T, unsigned __int128>::value,
std::true_type,
std::false_type>::type;
template <class T>
using make_unsigned_int128 =
typename std::conditional<std::is_same<T, __int128_t>::value,
__uint128_t,
unsigned __int128>;
template <class T>
using is_integral = typename std::conditional<std::is_integral<T>::value ||
is_signed_int128<T>::value ||
is_unsigned_int128<T>::value,
std::true_type,
std::false_type>::type;
template <class T>
using is_signed_int = typename std::conditional<(is_integral<T>::value &&
std::is_signed<T>::value) ||
is_signed_int128<T>::value,
std::true_type,
std::false_type>::type;
template <class T>
using is_unsigned_int =
typename std::conditional<(is_integral<T>::value &&
std::is_unsigned<T>::value) ||
is_unsigned_int128<T>::value,
std::true_type,
std::false_type>::type;
template <class T>
using to_unsigned = typename std::conditional<
is_signed_int128<T>::value,
make_unsigned_int128<T>,
typename std::conditional<std::is_signed<T>::value,
std::make_unsigned<T>,
std::common_type<T>>::type>::type;
#else
template <class T> using is_integral = typename std::is_integral<T>;
template <class T>
using is_signed_int =
typename std::conditional<is_integral<T>::value && std::is_signed<T>::value,
std::true_type,
std::false_type>::type;
template <class T>
using is_unsigned_int =
typename std::conditional<is_integral<T>::value &&
std::is_unsigned<T>::value,
std::true_type,
std::false_type>::type;
template <class T>
using to_unsigned = typename std::conditional<is_signed_int<T>::value,
std::make_unsigned<T>,
std::common_type<T>>::type;
#endif
template <class T>
using is_signed_int_t = std::enable_if_t<is_signed_int<T>::value>;
template <class T>
using is_unsigned_int_t = std::enable_if_t<is_unsigned_int<T>::value>;
template <class T> using to_unsigned_t = typename to_unsigned<T>::type;
} // namespace internal
} // namespace atcoder
#include <cassert>
#include <vector>
namespace atcoder {
// Reference: https://en.wikipedia.org/wiki/Fenwick_tree
template <class T> struct fenwick_tree {
using U = internal::to_unsigned_t<T>;
public:
fenwick_tree() : _n(0) {}
fenwick_tree(int n) : _n(n), data(n) {}
void add(int p, T x) {
assert(0 <= p && p < _n);
p++;
while (p <= _n) {
data[p - 1] += U(x);
p += p & -p;
}
}
T sum(int l, int r) {
assert(0 <= l && l <= r && r <= _n);
return sum(r) - sum(l);
}
private:
int _n;
std::vector<U> data;
U sum(int r) {
U s = 0;
while (r > 0) {
s += data[r - 1];
r -= r & -r;
}
return s;
}
};
} // namespace atcoder
using namespace std;
using namespace atcoder;
typedef long long ll;
typedef unsigned long long ull;
typedef pair<int,int> iint;
typedef pair<ll,ll> llll;
#define ALL(x) (x).begin(),(x).end()
const ll zero = 0;
const ll one = 1;
const ll INF = 9223372036854775807; //10^18
const int inINF = 2147483647; //10^9
const ll MOD = 998244353;
void Yes() {printf("Yes\n");}
void No() {printf("No\n");}
void YES() {printf("YES\n");}
void NO() {printf("NO\n");}
int main(){
int N;
cin >> N;
vector<ll> A(N);
for (int i = 0; i < N; i++) {
cin >> A[i];
}
map<ll, int> m;
for (int i = 0; i < N; i++) {
m[A[i]] = 1;
}
int ind = 1;
for (auto v : m){
m[v.first] = ind;
ind++;
}
fenwick_tree<ll> f1(N+2);
fenwick_tree<ll> f2(N+2);
vector<int> B(N);
for (ll i = 0; i < N; i++) {
B[i] = m[A[i]];
}
ll ans = 0;
vector<ll> I(N), J(N), K(N), L(N), R(N);
for (int i = 0; i < N; i++) {
K[i] = f2.sum(B[i] + 1, N+1);
L[i] = f1.sum(B[i] + 1, N+1);
f1.add(B[i], 1);
f2.add(B[i], f1.sum(B[i] + 1, N+1));
}
fenwick_tree<ll> f3(N+2);
fenwick_tree<ll> f4(N+2);
for (int i = N-1; i >= 0; i--) {
I[i] = f4.sum(0, B[i]);
R[i] = f3.sum(0, B[i]);
f3.add(B[i], 1);
f4.add(B[i], f3.sum(0, B[i]));
}
for (ll i = 0; i < N; i++) {
J[i] = L[i] * R[i] % MOD;
I[i] %= MOD;
K[i] %= MOD;
}
// for (int i = 0; i < N; i++) {
// printf("%d %lld %d %lld %lld %lld\n", i, A[i], B[i], I[i], J[i], K[i]);
// }
// for (int i = 1; i < 4; i++) {
// printf("%d %lld %lld %lld %lld\n", i, f1.sum(i, i+1), f2.sum(i, i+1), f3.sum(i, i+1), f4.sum(i, i+1));
// }
for (ll i = 0; i < N; i++) {
ans = (ans + A[i] * (I[i] + J[i] + K[i])) % MOD;
}
printf("%lld\n", ans);
}