Golang | Leetcode Golang题解之第446题等差数列划分II-子序列
题目：
题解：
func numberOfArithmeticSlices(nums []int) (ans int) {
f := make([]map[int]int, len(nums))
for i, x := range nums {
f[i] = map[int]int{}
for j, y := range nums[:i] {
d := x - y
cnt := f[j][d]
ans += cnt
f[i][d] += cnt + 1
}
}
return
}