mod = 1000000007
eps = 10**-9


def main():
    import sys
    input = sys.stdin.readline

    for _ in range(int(input())):
        N, M = map(int, input().split())
        if M == 1:
            print(0)
            continue
        if M <= N:
            print((M + 1) // 2)
        elif M == 2 * N:
            print(N - 1 + N * (N + 1) // 2 - 1)
        else:
            K = M - N - 1
            if K == 0:
                print((N - K + 1) // 2)
            elif K == 1:
                print((N - K + 1) // 2 + 3)
            else:
                print((N - K + 1) // 2 + K - 1 + K * (K + 1) // 2 - 1 + K + 2)


if __name__ == '__main__':
    main()