题解 | 牛牛学数列4
牛牛学数列4
https://www.nowcoder.com/practice/586b114f52034688879342ba45779081
package main
import (
"fmt"
)
func main() {
var n int
fmt.Scan(&n)
res := 0
for i := 1; i <= n; i++ {
res += sum(i)
}
fmt.Print(res)
}
func sum(n int) int {
if n == 1 {
return 1
}
res := make([]int, 2)
res[0] = 1
for i := 2; i <= n; i++ {
res[1] = res[0] + i
res[0] = res[1]
}
return res[1]
}