package main import ( "math" "log" "fmt" ) func main() { log.SetFlags(log.Lshortfile) var n int fmt.Scan(&n) x := make([]int, n+2) y := make([]int, n+2) for i:=1; i'z' { // fmt.Println("No") // return // } // }else{ // if b[i]!=' '{ // fmt.Println("No") // return // } // } // } // fmt.Println("Yes") } var dy = []int{0, 1, 0, -1} var dx = []int{1, 0, -1, 0} var inf = int(1e9) func pow(a, b int) int { return int(math.Pow(float64(a), float64(b))) } func lcm(a, b int) int { return a * b / gcd(a, b) } func gcd(a, b int) int { if a < b { a, b = b, a } for b != 0 { a, b = b, a%b } return a } func max(a ...int) int { r := a[0] for i := 0; i < len(a); i++ { if r < a[i] { r = a[i] } } return r } func min(a ...int) int { r := a[0] for i := 0; i < len(a); i++ { if r > a[i] { r = a[i] } } return r } func sum(a []int) (r int) { for i := range a { r += a[i] } return r } func abs(a int) int { if a < 0 { return -a } return a } type pair struct { a, b int } type pairs []pair func (p pairs) Len() int { return len(p) } func (p pairs) Swap(i, j int) { p[i], p[j] = p[j], p[i] } func (p pairs) Less(i, j int) bool { if p[i].a == p[j].a { return p[i].b < p[j].b } return p[i].a < p[j].a }