#Equilibrium Point


def equilibrium_point(arr):
    total_sum = sum(arr)
    left_sum = 0

    for i in range(len(arr)):
        total_sum -= arr[i]

        if left_sum == total_sum:
            return i

        left_sum += arr[i]

    return -1


# Example usage
array = [1, 2, 3, 4, 5, 5, 1, 1]
equilibrium = equilibrium_point(array)

if equilibrium != -1:
    print("Equilibrium point found at index", equilibrium)
else:
    print("No equilibrium point found in the array.")
