class calDifference{

	public static void main(String k[]){
	
	int n, sumOfSq, sqOfSums, diff;
	int[] num; 
	int[] numSq;	

	Scanner sc=new Scanner(System.in);
	
	System.out.println("Enter the num of Elements to be entered");
	n=sc.nextInt();
	
	num=new int[n];
	numSq=new int[n];

	inputElements(num);
	sqOfElememnts(num,numsq);
	sumOfSq = sum(numSq) * sum(numSq);
	sqOfSums =sum(num) * sum(num);	
	diff= sumOfSq - sqOfSums;

	public static void inputElements(int a[]){
		
		for(int i=0; i<n;i++){
		a[i]=sc.nextInt();
		}
	}
	
	public static void sqOfElements(int a[],int aSq[]){
		
		for(int i=0 ; i<n ; i++){
		aSq[i] = a[i] * a[i];
		}
	}

	public static int sum(int a[]){
		
	int sum = 0;
		for(int i=0; i<n;i++){
		sum = sum + a[i];
		}
	}


}

}