import sys
input = sys.stdin.readline
def read_values(): return map(int, input().split())
def read_index(): return map(lambda x: int(x) - 1, input().split())
def read_list(): return list(read_values())
import math


def calc(x,m,a,b,c,d):
  return a*x+(c*x+d)//m*b
def dfs(n,m,a,b,c,d):
  if n==0 or m==0:
    return -10**100
  add=d//m*b
  a+=c//m*b
  c%=m
  d%=m
  tmp=max(calc(0,m,a,b,c,d),calc(n-1,m,a,b,c,d))
  p=(c*(n-1)+d)//m
  if a >= 0:
    return max(tmp,dfs(p,c,b,a,m,m-d-1))+add
  else:
    return max(tmp,dfs(p,c,b,a,m,m-d-1)+a+b)+add
  
def main():
  n,m,a,b,c,d=read_values()
  print(dfs(n,m,a,b,c,d))
  return

if __name__ == "__main__":
  t=int(input())
  for _ in range(t):
    main()