def min_turns(h, d):
    position = 0
    health = h
    turns = 0
    cons_moves = 0
 
    while position < d:
        next_move_cost = cons_moves + 1
        if health >= next_move_cost:
            position += 1
            health -= next_move_cost
            cons_moves += 1
            turns += 1
        else:
            health += 1
            cons_moves = 0
            turns += 1
 
    print(turns)
t = int(input())
for _ in range(t):
	h,d = map(int,input().split())
	min_turns(h,d)

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NQozIDIKMSAxCjUgMwoyIDQKMTAgNw==

5
3 2
1 1
5 3
2 4
10 7