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#include "message.h"
#include "teatr.h"
#include <cstdio>
using namespace std;

#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define REP(i,n) FOR(i,0,n)

typedef long long LL;

int t[1 << 21];

void inc(int x) {
	x += 1 << 20;
	while (x) {
		++t[x];
		x >>= 1;
	}
}

int get(int x, int l, int a, int b) {
	int s = x - (1 << l) << 20 - l;
	int e = s + (1 << 20 - l);
	if (a == s && b == e) return t[x];
	int m = (s + e) >> 1;
	int r = 0;
	if (a < m) r += get(x << 1, l + 1, a, m);
	if (b > m) r += get((x << 1) + 1, l + 1, m, b);
	return r;
}

int main() {
	if (MyNodeId()) return 0;
	int n = GetN();
	LL r = 0;
	REP(i,n) {
		int x = GetElement(i) - 1;
		r += get(1, 0, x + 1, 1000000);
		inc(x);
	}
	printf("%d\n", r);
}