points1

#include <cstdio>
#include <cstdlib>
using namespace std;

int main()
{
    FILE *f=fopen("points.in","r");
    FILE *g=fopen("points.out","w");
    long long n=0;
    int r,x0,y0,x1,y1,x;
    fscanf(f,"%d",&r);
    for(x0=0,y0=r,x1=0,y1=r;x0!=r;x0=x1,y0=y1)
    {
        int circ=0,yCirc=y0,line=0,yLine=y0;
        /// gasim urmatorul punct (x1, y1) pe cerc, mentinand
        /// limita inferiosara din cerc
        do
        {
            circ +=2*x1+1,++x1;
            while(circ>0)
                circ-=2*y1-1,--y1;
        } while(circ);
        /// adaugam contributia pentru punctele (x, *) cu x0 <= x < x1
        /// acest lucru poate fi calculat usor prin mentinerea limitei inferioare
        /// pentru cerc si linia (x0, y0) <-> (x1, y1)
        for(x=x0;x<x1;++x)
        {
            circ+=2*x+1;
            while(circ>0)
                circ-=2*yCirc-1,--yCirc;
            line-=y1-y0;
            while(line>0)
                line-=x1-x0,--yLine;
            n+=yCirc-yLine;
        }
    }
    fprintf(g,"%lld",4*n);
    fclose(f);
    fclose(g);
    return 0;
}