time complexity

Question

main()
{
    int i,count;
    for (i=1; i<=n; i++)
    {
        for(i=1; i<=(n*n); i++)
        {
            for(i=1; i<=(n*n*n); i++)
            {
              count++;  
            }
        }
    }
}

What will be the time complexity of the given program?

Answer 1

its O(n³) as the program reaches first time in the third loop it runs for i = n³. and when it comes back to loop2 it finds out that i>n² now when it comes back to loop 1 it gets i>n so it terminates out making time complexity to be O(n³).

Comments

Thank You

---

bdw its a good question :)

Answer 2

O(n^3)

because i is common for all three loops .

so

first loop first iteration i=1

second loop first iteration i=1;

third loop i=1   1<n^3

               i=2

            .........................................................

             i=n^3+1<=n^3   false(exit from 3rd loop) till now n^3 times loop is run.       

   n^3+2<n^2  false(exit from second loop)

 n^3+3<n  false(exit from first loop)

soO(n^3)