Adding Squares

addingsquares.py

line = []
n = int(input())
for i in range(n):
    line.append(input())
    
if len(line) != 1:
    a = sum([int(i) for i in line[0].split()])
    b = sum([int(i) for i in line[n-1].split()])
    c = 0
    for i in range(len(line)-2):
        data = [int(i) for i in line[i+1].split()]
        c+=data[0]
        c+=data[n-1]
    print(a+b+c)
else:
    print(line[0])