why is my solution not passing two test cases ?

a=[]

b=[]

result=[]

for av in range(int(input())):

x,y,z=map(int,input().split())

a.append(x)

b.append(y+z)

su=sum(a)

for i in range(len(a)):

result.append(su+b[i])

print(min(result))

Can maximum nesting depth be equal to maximum no. of symbols between two brackets in this problem.