a = input()
b = a.split(' ')
N = int(b[0])
K = int(b[1])
c = 0
Players = [i + 1 for i in range(N)]
while len(Players) != 1:
    for i in range(K):
        c = c % N + 1
    Players.pop(c - 1)
    N -= 1
    c -= 1
print(Players[0])