import sys sys.setrecursionlimit(10**6) int1 = lambda x: int(x)-1 p2D = lambda x: print(*x, sep="\n") def II(): return int(sys.stdin.buffer.readline()) def LI(): return list(map(int, sys.stdin.buffer.readline().split())) def LI1(): return list(map(int1, sys.stdin.buffer.readline().split())) def LLI(rows_number): return [LI() for _ in range(rows_number)] def LLI1(rows_number): return [LI1() for _ in range(rows_number)] def BI(): return sys.stdin.buffer.readline().rstrip() def SI(): return sys.stdin.buffer.readline().rstrip().decode() # dij = [(0, 1), (-1, 0), (0, -1), (1, 0)] dij = [(0, 1), (-1, 0), (0, -1), (1, 0), (1, 1), (1, -1), (-1, 1), (-1, -1)] inf = 10**16 md = 998244353 # md = 10**9+7 from math import atan2 from bisect import * n=II() xy=LLI(n) rxy=[(atan2(y,x),x,y) for x,y in xy] rr=[r for r,x,y in rxy] rxy.sort(key=lambda x:x[0]) rr.sort() # print(rxy) # print(rr) def rev(i): r,x,y=rxy[i] return atan2(-y,-x),-x,-y ans=0 for j in range(n): for i in range(j): r1,x1,y1=rev(i) r2,x2,y2=rev(j) s=x1*y2-y1*x2 if s==0:continue if s<0:r1,r2=r2,r1 l=bisect_right(rr,r1) r=bisect_left(rr,r2) if l<=r:ans+=r-l else:ans+=n-l+r # print(i,j,l,r,ans) print(ans//3)