package fac func Factorial(n int) int { res := 1 for i := 1; i <= n; i++ { res *= i	} return res }

package fac func Factorial(n int) int { if n == 0 { return 1	} else { return Factorial(n - 1) * n	} }

package fac func Factorial(n interface{}) interface{} { v, valid := n.(int) if !valid { return 0	} res := 1 for i := 1; i <= v; i++ { res *= i	} return res }

package fac import "sync" func Factorial(n int) int { var ( left, right = 1, 1 wg sync.WaitGroup	) wg.Add(2) pivot := n / 2 go func() { for i := 1; i < pivot; i++ { left *= i	} wg.Done()	}() go func() { for i := pivot; i <= n; i++ { right *= i	} wg.Done()	}() wg.Wait() return left * right }

package fac func Factorial(n int) <-chan int { ch := make(chan int) go func() { prev := 1 for i := 1; i <= n; i++ { v := prev * i ch <- v prev = v	} close(ch)	}() return ch }

package fac /**  * @see https://en.wikipedia.org/wiki/Factorial  */ type IFactorial interface { CalculateFactorial() int } // FactorialImpl implements IFactorial. var _ IFactorial = (*FactorialImpl)(nil) /**  * Used to find factorial of the n.  */ type FactorialImpl struct { /**  * The n.  */ n int } /**  * Constructor of the FactorialImpl.  *  * @param n the n.  */ func NewFactorial(n int) *FactorialImpl { return &FactorialImpl{ n: n,	} } /**  * Gets the n to use in factorial function.  *  * @return int.  */ func (this *FactorialImpl) GetN() int { return this.n } /**  * Sets the n to use in factorial function.  *  * @param n the n.  * @return void.  */ func (this *FactorialImpl) SetN(n int) { this.n = n } /**  * Returns factorial of the n.  *  * @todo remove "if" statement. Maybe we should use a factory or somthing?  *  * @return int.  */ func (this *FactorialImpl) CalculateFactorial() int { if this.n == 0 { return 1	} n := this.n this.n = this.n - 1 return this.CalculateFactorial() * n }

package fac // Factorial returns n!. func Factorial(n int) int { res := 1 for i := 1; i <= n; i++ { res *= i	} return res }