def solve(l):
n,m = l
if n<0 or m <0 or m >n:
return 0
if m == 0 or n == m or n<=1:
return 1
k = n-1
s = 1
for i in range(m):
s += k
k -= 2
return s
for _ in range(int(input())):
print(solve(map(int,input().split())))