Freewheel 4.16笔试 第三题代码
笔试时间紧张，代码写得比较暴力粗糙，仅供没AC的小伙伴找问题，勿喷哈。
package main
import (
"fmt"
"math"
)
func longestGeometricSeqLength(nums []int) int {
// write code here
if len(nums) == 0 {
return 0
}
s1 := solution(nums)
left, right := 0, len(nums)-1
for left < right {
nums[left], nums[right] = nums[right], nums[left]
left++
right--
}
s2 := solution(nums)
ans := s1
if s2 > ans {
ans = s2
}
if ans == math.MinInt64 {
ans = 1
}
return ans
}
func solution(nums []int) int {
n := len(nums)
dp := make([]map[int]int, n)
// dp:=make(map[int]map[int]int) // 下标 - 比例 - 最长长度
dp[0] = make(map[int]int)
ans := math.MinInt64
for i := 1; i < n; i++ {
dp[i] = make(map[int]int)
for j := i - 1; j >= 0; j-- {
if nums[j] != 0 && nums[i]%nums[j] == 0 {
vv := nums[i] / nums[j]
preLength, ok := dp[j][vv]
//fmt.Println(preLength, ok)
newLength := 0
if !ok {
newLength = 2
} else {
newLength = preLength + 1
}
if curLength, ok := dp[i][vv]; !ok {
dp[i][vv] = newLength
} else if newLength > curLength {
dp[i][vv] = newLength
}
if dp[i][vv] > ans {
ans = dp[i][vv]
}
}
}
//fmt.Println(i, dp[i])
}
return ans
}
func main() {
ans := longestGeometricSeqLength([]int{2, 3})
fmt.Println(ans)
} 
