Question: 
Write a function to find the largest sum of contiguous array in the modified array which is formed by repeating the given array k times.


Model's Code:
def max_sub_array_sum_repeated(arr, k, m):
    def kadane(nums):
        max_ending_here = max_so_far = nums[0]
        for x in nums[1:]:
            max_ending_here = max(x, max_ending_here + x)
            max_so_far = max(max_so_far, max_ending_here)
        return max_so_far

    n = len(arr)
    total_sum = sum(arr)
    
    if k == 1:
        return kadane(arr)
    
    max_kadane = kadane(arr)
    max_prefix_sum = float('-inf')
    current_prefix_sum = 0
    
    for i in range(n):
        current_prefix_sum += arr[i]
        max_prefix_sum = max(max_prefix_sum, current_prefix_sum)
    
    max_suffix_sum = float('-inf')
    current_suffix_sum = 0
    
    for i in range(n-1, -1, -1):
        current_suffix_sum += arr[i]
        max_suffix_sum = max(max_suffix_sum, current_suffix_sum)
    
    if total_sum > 0:
        return max(max_kadane, max_suffix_sum + (k - 2) * total_sum + max_prefix_sum)
    else:
        return max(max_kadane, max_suffix_sum + max_prefix_sum)



Sample Correct Code:
def max_sub_array_sum_repeated(a, n, k): 
	max_so_far = -2147483648
	max_ending_here = 0
	for i in range(n*k): 
		max_ending_here = max_ending_here + a[i%n] 
		if (max_so_far < max_ending_here): 
			max_so_far = max_ending_here 
		if (max_ending_here < 0): 
			max_ending_here = 0
	return max_so_far


Asserts:
assert max_sub_array_sum_repeated([10, 20, -30, -1], 4, 3) == 30
assert max_sub_array_sum_repeated([-1, 10, 20], 3, 2) == 59
assert max_sub_array_sum_repeated([-1, -2, -3], 3, 3) == -1


Tests:
Test 1 of 3: PASS
Test 2 of 3: FAIL: AssertionError()

Test 286 of 974: 205/286 (71.67832167832168%): failed