快乐数

2020-05-05 本文已影响0人 7赢月

题目描述

https://leetcode-cn.com/problems/happy-number/

解

package main

func isHappy(n int) bool {
    var (
        filter = make(map[int]struct{})
        c      = 0
    )
    for {
        r := n % 10
        c += r * r
        n = n / 10
        if n != 0 {
            continue
        }
        if c == 1 {
            return true
        }
        if _, ok := filter[c]; ok {
            return false
        }
        filter[c] = struct{}{}
        n = c
        c = 0
    }
}