32 lines
414 B
Go
32 lines
414 B
Go
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package Recursion
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// 迭代实现阶乘
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type Fac struct {
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val map[int]int
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}
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func NewFactorial(n int) *Fac {
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return &Fac{
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make(map[int]int, n),
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}
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}
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func (fac *Fac) Factorial(n int) int {
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if fac.val[n] != 0{
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return fac.val[n]
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}
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if n <= 1{
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fac.val[n] = 1
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return 1
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}else {
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res := n * fac.Factorial(n-1)
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fac.val[n] =res
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return res
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}
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}
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func (fac *Fac) Print(n int ) {
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println(fac.val[n])
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}
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