The main method I followed was to first compare two of the arrays and extract the similar values in another array. I then compared that array with the third array, and updated the counter each time there was a match in eigenvalues. This method avoids comparing all the arrays together, and hence takes up less time. So in essence number of operations reduces to O(2*N^2) instead of O(N^3). However, more sophisticated algorithms like binary search are more effective. But still I include this method for people like myself, who are new to algorithms. Hope it helps someone.

Thank you! Did as you said and get Accepted))
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