Time Complexity of Code snippet

Question

What will be the worst case time complexity for the following code segment?

int count=0,N;
for(i=0;i<N*2;i++){
    for(j=0;j<i/3;i++){
        for(k=0;k<j*j;k++){
            count++;
        }
    }
}

Options:

1. O(N^4)
2. O(N^3)
3. O(N^2)
4. O(N)

Answer 1

int count=0,N; --------(1)

for(i=0;i<N*2;i++){     ----->0(n)  

for(j=0;j<i/3;i++){   0(n/3)

for(k=0;k<j*j;k++){    0((n*n)/3)

count++;

}

}

}

HEre we are using the for loop so that 0(n*(n/3)*(n*n)/3) so that 0(n^4)

Answers is A