comparison maths/MathUtilities.cpp @ 135:0fdbb93e92b7

Factorial: return double (int not big enough for many popular values)

     int n0 = previousPowerOfTwo(x), n1 = nextPowerOfTwo(x);
     if (x - n0 < n1 - x) return n0;
     else return n1;
 }
 
-int
+double
 MathUtilities::factorial(int x)
 {
     if (x < 0) return 0;
-    int f = 1;
+    double f = 1;
     for (int i = 1; i <= x; ++i) {
 	f = f * i;
     }
     return f;
 }