帖子def nCr(n,k):

def nCr(n,k): if k<0 or k>n: return 0 k=min(k,n-k) res=1 for i in range(1,k+1): res=res*(n-k+i)//i return res T=int(input().strip()) for i in range(T): parts=input().split() k=int(parts[0]) s=parts[1].strip() d=len(set(s)) print(nCr(d,k)) SPRINKLER✅✅