Equilibrium index of an array is an index such that the sum of elements at lower indexes is equal to the sum of elements at higher indexes . Now Given an array your task is to complete the function findEquilibrium which returns the index of the first Equilibrium point in the array. The function takes two arguments. The first argument is the array A[ ] and the second argument is the size of the array A.
The first line of input takes an integer T denoting the no of test cases, then T test cases follow. The first line of each test case is an integer N denoting The size of the array . Then in the next line are N space separated values of the array.
For each test case output will be the equilibrium index of the array .If no such index exist output will be -1.
Example(To be used only for expected output):
1 2 0 3
1 1 1 1
Note:The Input/Ouput format and Example given are used for system's internal purpose, and should be used by a user for Expected Output only. As it is a function problem, hence a user should not read any input from stdin/console. The task is to complete the function specified, and not to write the full code.