C++ :

#include <stdio.h>

#include <algorithm>
#include <iostream>

typedef long long llong;

llong div(llong a, llong b)
{
  return (a + b-1) / b;
}

void maxlis(llong &x, llong a)
{
  x = std::max(x, a);
}

llong a, b, x, y, m;

llong max_hurt(llong k)
{
  llong h = x * k;
  if (k == 1)
    return h;
  maxlis(h, (k-1) * x + a + b * (k-1));
  llong z = (a+b) + x * y;
  llong zcnt = k / (y+1);
  if (k % (y+1) == 0) {
    maxlis(h, z * (zcnt - 1) + y * x + a + y * b);
  }
  else if (k % (y+1) == 1) {
    maxlis(h, z * (zcnt - 1) + (y+1) * x + a + (y+1) * b);
  }
  else if (k % (y+1) == 2) {
    maxlis(h, z * zcnt + x + a + b);
  }
  else {
    llong r = k % (y+1);
    maxlis(h, z * zcnt + (r-1) * x + a + b * (r-1));
  }
  return h;
}

int main()
{
  //freopen("../data/E.in", "r", stdin);
  //freopen("../data/tmpE.out", "w", stdout);
  int casc;
  scanf("%d", &casc);
  for (int casi =1 ; casi <= casc; ++casi) {
    //scanf("%I64d %I64d %I64d %I64d %I64d", &a, &b, &x, &y, &m);
    std::cin >> a >> b >> x >> y >> m;
    llong l = 0;
    llong r = m;
    // [r, l)
    //std::cout << max_hurt(32LL) << "\n";
    for (; r-l > 1; ) {
      llong mid = (l+r) >> 1;
      llong now = max_hurt(mid);
      if (now >= m)
        r = mid;
      else l = mid;
    }
    //printf("%I64d\n", r);
    std::cout << r << std::endl;
  }
  return 0;
}