climbStairs

climb_stairs.rb

# Runtime: 32 ms, faster than 68.51% of Ruby online submissions for Climbing Stairs.
# Memory Usage: 9.3 MB, less than 100.00% of Ruby online submissions for Climbing Stairs.
# https://leetcode.com/problems/climbing-stairs/submissions/
def cs(i,n,mem)
    return 0 if i > n
    return 1 if i == n
    return mem[i] if mem[i]
    mem[i] = cs(i+1, n, mem) + cs(i+2,n,mem)
end
def climb_stairs(n)
    mem = {}
    cs(0,n,mem)
end

climbStairs.go

// https://leetcode.com/problems/climbing-stairs/
// Time limit exceed
func climbStairs(n int) int {
    counter := 0
    // https://gobyexample.com/closures
    // https://github.com/golang/go/issues/226
    var recursion func(input int)
    recursion = func (input int){
        if 0 == input {
            counter += 1
        }
        if 0 > input {
            return
        }
        recursion(input - 1)
        recursion(input - 2)
    }
    recursion(n)
    return counter
    
}