import sys
import math

def main():
    input = sys.stdin.read().split()
    idx = 0
    N = int(input[idx])
    idx += 1
    points = []
    for _ in range(N):
        x = int(input[idx])
        y = int(input[idx+1])
        points.append((x, y))
        idx += 2
    
    result = 0
    for i in range(N):
        xi, yi = points[i]
        dir_counts = {}
        for j in range(N):
            if i == j:
                continue
            xj, yj = points[j]
            dx = xj - xi
            dy = yj - yi
            g = math.gcd(abs(dx), abs(dy))
            if g == 0:
                continue  # Not possible as per problem constraints
            reduced = (dx // g, dy // g)
            if reduced in dir_counts:
                dir_counts[reduced] += 1
            else:
                dir_counts[reduced] = 1
        # Check if any direction has at least two points
        for count in dir_counts.values():
            if count >= 2:
                result += 1
                break
    print(result)

if __name__ == '__main__':
    main()