Uri 1030

t = int(input())
m = 0

while t > 0:
    m += 1
    n, k = map(int, input().split(' '))
    l = list(range(1, n+1))
    k -= 1
    temp = k
    while len(l) > 1:
        if k < len(l):
            l.pop(k)

        else:
            k = k%(len(l))
            l.pop(k)

        k += temp

    print("Case", str(m)+':', l[0])

    t -= 1