f = lambda: map(int, input().split())
A, B, n = f()
k = 0.5
for i in range(n):
l, t, m = f()
b = A / B + l - k
c = b - k - (m * t) / B
r = min(l + int((b * b - 2 * c) ** k - b), (t - A) // B + 1)
print(-1 if r < l else r)1633C - Kill the Monster | 1611A - Make Even |
1030B - Vasya and Cornfield | 1631A - Min Max Swap |
1296B - Food Buying | 133A - HQ9+ |
1650D - Twist the Permutation | 1209A - Paint the Numbers |
1234A - Equalize Prices Again | 1613A - Long Comparison |
1624B - Make AP | 660B - Seating On Bus |
405A - Gravity Flip | 499B - Lecture |
709A - Juicer | 1358C - Celex Update |
1466B - Last minute enhancements | 450B - Jzzhu and Sequences |
1582C - Grandma Capa Knits a Scarf | 492A - Vanya and Cubes |
217A - Ice Skating | 270A - Fancy Fence |
181A - Series of Crimes | 1638A - Reverse |
1654C - Alice and the Cake | 369A - Valera and Plates |
1626A - Equidistant Letters | 977D - Divide by three multiply by two |
1654B - Prefix Removals | 1654A - Maximum Cake Tastiness |