#include <stdio.h>

FILE*citire = fopen("cifra.in", "r");
FILE*scriere = fopen("cifra.out", "w");


int main()
{
	int i,n,s=0,lastDigit;


	fprintf(scriere,"n=");
	fscanf(citire,"%d",&n);

	for(i=1;i<=n;i++)
	{
		s=s+i*i;
	}


	fprintf(scriere,"Sum is: %d.\n", s);
	
	lastDigit = s % 10;

	fprintf(scriere,"Last digit is: %d.\n", lastDigit);
	
	fclose(citire);
	fclose(scriere);

	return 0;
}