n,m=map(int,input().split()) b=[] c=0 d=1 i=0 for i in range(n): b.append(1) while True: i+=1 if i>=n: i-=n if b[i]!=0: c+=1 if c==m: b[i]=0 c=0 d+=1 if d==n: for i in range(len(b)): if b[i]==1: print(i+1) break