import times, strutils, sequtils, math, algorithm, tables, sets, lists, intsets import critbits, future, strformat, deques,heapqueue template `max=`(x,y) = x = max(x,y) template `min=`(x,y) = x = min(x,y) template `mod=`(x,y) = x = x mod y template scan2 = (scan(), scan()) template scan3 = (scan(), scan()) let read* = iterator: string {.closure.} = while true: (for s in stdin.readLine.split: yield s) proc scan(): int = read().parseInt proc scanf(): float = read().parseFloat proc scanbf(): BiggestFloat = read().parseFloat proc toInt(c:char): int = return int(c) - int('0') proc xgcd(a,b:int):(int,int,int)= var b = b x0=1 y0=0 x1=0 y1=1 q:int a = a while b!=0: (q,a,b) = (a.div(b),b,a.mod(b)) (x0,x1)=(x1,x0-q*x1) (y0,y1)=(y1,y0-q*y1) return (a,x0,y0) # modの逆元 proc modinv(a,m:int):int= var (g,x,y)=xgcd(a,m) if g!=1: return -1 else: return ((x mod m)+m).mod(m) proc solve():int= var n = scan() es = newseqwith(n,newseq[int]()) fact = newseqwith(n+1,1) depth = newseqwith(n,int.high.div(4)) minv = newseqwith(n+1,0) md = 10^9+7 for i in 0..0: var p = q.popFirst for nxt in es[p]: if depth[nxt]>depth[p]+1: depth[nxt]=depth[p]+1 q.addLast(nxt) #echo depth for i in 0..