Polygon area

from sys import stdin,stdout,stderr

inpt = stdin.read().strip().split("\n")
count = int(inpt[0])

points = [None]*count
su = 0

last = tuple(int(aa) for aa in inpt[0+1].split(" "))
start = last
for ii in range(1,count):
    curr = tuple(int(aa) for aa in inpt[ii+1].split(" "))
    su += last[0]*curr[1] - curr[0]*last[1]
    last = curr

su += last[0]*start[1] - last[1]*start[0]


print(abs(su))

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED