import std.algorithm, std.container, std.conv, std.math, std.range, std.typecons, std.stdio, std.string;

auto rdsp(){return readln.splitter;}
void pick(R,T)(ref R r,ref T t){t=r.front.to!T;r.popFront;}
void readV(T...)(ref T t){auto r=rdsp;foreach(ref v;t)pick(r,v);}
void readC(T...)(size_t n,ref T t){foreach(ref v;t)v=new typeof(v)(n);foreach(i;0..n){auto r=rdsp;foreach(ref v;t)pick(r,v[i]);}}

void main()
{
  int n; readV(n);
  int[] m; readC(n, m);

  auto ft = new FenwickTree!int(n+1);

  auto r = 0L;
  foreach (mi; m) {
    r += ft[mi..$];
    ++ft[mi];
  }

  writeln(r);
}

class FenwickTree(T)
{
  const size_t n;
  T[] buf;

  this(size_t n)
  {
    this.n = n;
    this.buf = new T[](n+1);
  }

  void opIndexOpAssign(string op)(T val, size_t i) if (op == "+" || op == "-")
  {
    ++i;
    for (; i <= n; i += i & -i) mixin("buf[i] " ~ op ~ "= val;");
  }

  void opIndexUnary(string op)(size_t i) if (op == "++" || op == "--")
  {
    ++i;
    for (; i <= n; i += i & -i) mixin("buf[i]" ~ op ~ ";");
  }

  pure T opSlice(size_t r, size_t l) { return get(l) - get(r); }
  pure T opIndex(size_t i) { return opSlice(i, i+1); }
  pure size_t opDollar() { return n; }

private:

  pure T get(size_t i)
  {
    auto s = T(0);
    for (; i > 0; i -= i & -i) s += buf[i];
    return s;
  }
}