The program ns contains 4 nested loops, none of them are context sensitive.

The number of iterations of the loops in the program is input dependent (keys). The loops are always executed the same number of times.

When it is run as is, the result is

No. of iterations for main_foo_L1 = 5
Maximum no. of iterations per invocation for main_foo_L1_L1 is 5, sum is 25
Maximum no. of iterations per invocation for main_foo_L1_L1_L1 is 5, sum is 125
Maximum no. of iterations per invocation for main_foo_L1_L1_L1_L1 is 5, sum is 625