Check which numbers meet the condition [A*B*C = A! + B! + C!]

#understand 
#understand 
using namespace std;
int s = 1; //Serial number.

Should I use recursion for factorial function?

int Factorial (int n)
{
int k = 1;
for (int i = 1; i <= n; ++ i)
{
k = k * i;
}
returns k;
}

How can I do this in one loop instead of the 3 while loops?

int main ()
{
int a = 1;
int b = 1;
int c = 1;
int Fact1;
int Fact2;
int Fact3;
while (a <11)
{
Fact1 = Factorial (a);
while (b <11)
{
Fact2 = Factorial (b);
as long as (c <11)
{
Fact3 = Factorial (c);
cost << s << ":";
int LHS = Fact1 + Fact2 + Fact3;
if (LHS == a * b * c)
{
cost << "Pass:" << "" << << << << << << << << c << endl;
}
other
{
cost << "Fail" / * << "" << Fact1 << "" << Fact2 << "" << Fact3 * / << endl;
}
c ++;
s ++;
}
c = 1;
b ++;
}
b = 1;
a ++;
}
returns 0;
}

Also, I would like some variable naming tips.