#include <iostream>
using namespace std;
 
// Naive function to find minimum index of repeating element
int findMinIndex(int arr[], int n)
{
	// for each element arr[i], search it in sub-array arr[i+1..n-1]
	// and return as soon as first repeated occurrence is found
	for (int i = 0; i < n - 1; i++)
	{
		for (int j = i + 1; j < n; j++)
		{
			// if the element is seen before, return its index
			if (arr[j] == arr[i])
				return i;
		}
	}
 
	// invalid input
	return n;
}
 
// main function
int main()
{
	int arr[] = { 5, 6, 3, 4, 3, 6, 4 };
	// int arr[] = { 1, 2, 3, 4, 5, 6 };
 
	int n = sizeof(arr) / sizeof(arr[0]);
 
	int minIndex = findMinIndex(arr, n);
 
	if (minIndex != n)
		cout << "Minimum index of repeating element is " << minIndex;
	else
		cout << "Invalid Input";
 
	return 0;
}

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