n=int(input())
a=[]
for i in range(n):
    a.append(int(input()))
js=0
for i in range(n):
    for j in range(i+1,n):
        if(a[j]<a[i]):
            js=js+1
print(js)
/**************************************************************
	Problem: 1215
	User: admin
	Language: Python
	Result: Accepted
	Time:97 ms
	Memory:34480 kb
****************************************************************/