package main import ( "fmt" "math" "math/big" ) func main() { var n int _, _ = fmt.Scan(&n) sheep := func(i int) int { bi1 := big.NewInt(int64(i)) bi2 := big.NewInt(int64(i)) bi1.Mul(bi1, bi1) bi1.Add(bi1, bi2) bi1.Div(bi1, big.NewInt(2)) return int(bi1.Int64()) } i := 0 min, max := 1, int(math.Pow10(9))*2 for min != max { i = int(math.Ceil(float64(max-min)/2)) + min s := sheep(i) if s == n { min, max = i, i } else if s > n { max = i - 1 } else { min = i } if max == min { i = max } // fmt.Println(min, max, i, sheep(i), n) } if n == sheep(i) { fmt.Println("YES") fmt.Println(i) } else { fmt.Println("NO") } }