from collections import * from itertools import * from functools import * from heapq import * import sys,math # input = sys.stdin.readline N = int(input()) A = list(map(int,input().split())) # https://github.com/tatyam-prime/SortedSet/blob/main/SortedMultiset.py import math from bisect import bisect_left, bisect_right from typing import Generic, Iterable, Iterator, List, Tuple, TypeVar, Optional T = TypeVar('T') class SortedMultiset(Generic[T]): BUCKET_RATIO = 50 REBUILD_RATIO = 170 def _build(self, a: Optional[List[T]] = None) -> None: "Evenly divide `a` into buckets." if a is None: a = list(self) size = len(a) bucket_size = int(math.ceil(math.sqrt(size / self.BUCKET_RATIO))) self.a = [a[size * i // bucket_size : size * (i + 1) // bucket_size] for i in range(bucket_size)] def __init__(self, a: Iterable[T] = []) -> None: "Make a new SortedMultiset from iterable. / O(N) if sorted / O(N log N)" a = list(a) self.size = len(a) if not all(a[i] <= a[i + 1] for i in range(len(a) - 1)): a = sorted(a) self._build(a) def __iter__(self) -> Iterator[T]: for i in self.a: for j in i: yield j def __reversed__(self) -> Iterator[T]: for i in reversed(self.a): for j in reversed(i): yield j def __eq__(self, other) -> bool: return list(self) == list(other) def __len__(self) -> int: return self.size def __repr__(self) -> str: return "SortedMultiset" + str(self.a) def __str__(self) -> str: s = str(list(self)) return "{" + s[1 : len(s) - 1] + "}" def _position(self, x: T) -> Tuple[List[T], int]: "Find the bucket and position which x should be inserted. self must not be empty." for a in self.a: if x <= a[-1]: break return (a, bisect_left(a, x)) def __contains__(self, x: T) -> bool: if self.size == 0: return False a, i = self._position(x) return i != len(a) and a[i] == x def count(self, x: T) -> int: "Count the number of x." return self.index_right(x) - self.index(x) def add(self, x: T) -> None: "Add an element. / O(√N)" if self.size == 0: self.a = [[x]] self.size = 1 return a, i = self._position(x) a.insert(i, x) self.size += 1 if len(a) > len(self.a) * self.REBUILD_RATIO: self._build() def _pop(self, a: List[T], i: int) -> T: ans = a.pop(i) self.size -= 1 if not a: self._build() return ans def discard(self, x: T) -> bool: "Remove an element and return True if removed. / O(√N)" if self.size == 0: return False a, i = self._position(x) if i == len(a) or a[i] != x: return False self._pop(a, i) return True def lt(self, x: T) -> Optional[T]: "Find the largest element < x, or None if it doesn't exist." for a in reversed(self.a): if a[0] < x: return a[bisect_left(a, x) - 1] def le(self, x: T) -> Optional[T]: "Find the largest element <= x, or None if it doesn't exist." for a in reversed(self.a): if a[0] <= x: return a[bisect_right(a, x) - 1] def gt(self, x: T) -> Optional[T]: "Find the smallest element > x, or None if it doesn't exist." for a in self.a: if a[-1] > x: return a[bisect_right(a, x)] def ge(self, x: T) -> Optional[T]: "Find the smallest element >= x, or None if it doesn't exist." for a in self.a: if a[-1] >= x: return a[bisect_left(a, x)] def __getitem__(self, i: int) -> T: "Return the i-th element." if i < 0: for a in reversed(self.a): i += len(a) if i >= 0: return a[i] else: for a in self.a: if i < len(a): return a[i] i -= len(a) raise IndexError def pop(self, i: int = -1) -> T: "Pop and return the i-th element." if i < 0: for a in reversed(self.a): i += len(a) if i >= 0: return self._pop(a, i) else: for a in self.a: if i < len(a): return self._pop(a, i) i -= len(a) raise IndexError def index(self, x: T) -> int: "Count the number of elements < x." ans = 0 for a in self.a: if a[-1] >= x: return ans + bisect_left(a, x) ans += len(a) return ans def index_right(self, x: T) -> int: "Count the number of elements <= x." ans = 0 for a in self.a: if a[-1] > x: return ans + bisect_right(a, x) ans += len(a) return ans X = SortedMultiset() Y = SortedMultiset() X.add(A[0]) if N<=2: print(0) exit() ans = 0 for i in range(2,N): Y.add(A[i]) for i in range(1,N-1): a = A[i] ans += X.index(a)*Y.index(a) + (i - X.index_right(a))*(N-1-i - Y.index_right(a)) X.add(a) Y.discard(A[i+1]) Z = defaultdict(lambda:[]) for i,a in enumerate(A): Z[a].append(i) for v in Z.values(): k = len(v) for j in range(k-1): ans -= (v[j+1]-v[j]-1)*(j+1)*(k-1-j) print(ans)