#include <iostream>
using namespace std;
int suma_div(int nr)
{
    int d,sum=1;
    for (d=2; d*d<=nr; d++)
        if (nr%d==0)
            sum += d;
    if (sum == nr)
        return sum;
    else
        return -1;
}
int main()
{
    int i,a,b,suma=0,s;
    cin>>a>>b;
    for (i=a; i<=b; i++)
    {
        s = suma_div(i) + 1;
        if (s > 0)
            suma += i;
    }
    cout<<suma;
}





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#include <iostream>
using namespace std;
#include <math.h>
float aria_cerc(int R, int h)
{
    return 2*3.14*R*h+3.14*R*R;
}
float volum_cerc(int R, int h)
{
    return 3.14*R*R*h;
}
float aria_dreptunghi(int l, int L, int h)
{
    return 2*(L+l)*h + l*L;
}
float volum_dreptunghi(int l, int L, int h)
{
    return L*l*h;
}
float aria_patrat(int l, int h)
{
    return 4*l*h+l*l;
}
float volum_patrat(int l, int h)
{
    return l*l*h;
}
float aria_triunghi(int c1, int c2, int h)
{
    return (c1+c2+sqrt(c1*c1+c2*c2))*h + c1*c2/2.0;
}
float volum_triunghi(int c1,int c2, int h)
{
    return c1*c2*h/2.0;
}
int main()
{
    int
}