#include <bits/stdc++.h>
using namespace std;
void read_file(bool outToFile = true) {}
struct point;
struct vec;
struct line;
struct circle;
struct triangle;
double to_rad(double theta);
double to_deg(double theta);
double dist(point p, point q);
point middle(point p, point q);
point translate(point p, vec u);
double norm_sq(vec u);
double dot(vec u, vec v);
double cross(vec u, vec v);
bool are_parallel(line l, line d);
bool are_same(line l, line d);
double dist_to_line(point p, point a, point b);
bool ccw(point p, point q, point r);
bool collinear(point p, point q, point r);
double angle(point a, point o, point b);
point rotate(point p, double theta, point q);
point intersection(line l, line d);
point projection(point p, point a, point b);
double dist_to_segment(point p, point a, point b);
point reflection(point p, point a, point b);
line perpendicular(point p, point a, point b);
line bisector(point a, point o, point b);
circle find_circle(point p, point q, double r);
circle in_circle(triangle t);
circle circum_circle(triangle t);
double perimeter(vector<point> P);
double area(vector<point> P);
bool is_convex(vector<point> P);
bool is_in(point p, vector<point> P);
vector<point> cut(vector<point> P, point a, point b);
bool ch_cmp(point a, point b);
vector<point> convex_hull(vector<point> P);
struct point {
  double x, y;
  point(double nx = 0, double ny = 0) { x = nx, y = ny; }
  bool operator==(point p) {
    return fabs(x - p.x) <= (1e-9) && fabs(y - p.y) <= (1e-9);
  }
  bool operator!=(point p) {
    return fabs(x - p.x) > (1e-9) || fabs(y - p.y) > (1e-9);
  }
  bool operator<(point p) {
    if (fabs(x - p.x) > (1e-9)) return x < p.x - (1e-9);
    return y < p.y - (1e-9);
  }
  friend istream &operator>>(istream &is, point &p) { return is >> p.x >> p.y; }
  friend ostream &operator<<(ostream &os, point &p) {
    return os << p.x << ' ' << p.y;
  }
};
struct vec {
  double x, y;
  vec(double nx = 0, double ny = 0) { x = nx, y = ny; }
  vec(point p, point q) { x = q.x - p.x, y = q.y - p.y; }
  vec operator+(vec u) { return vec(x + u.x, y + u.y); }
  vec operator-(vec u) { return vec(x - u.x, y - u.y); }
  vec operator*(double k) { return vec(k * x, k * y); }
  friend istream &operator>>(istream &is, vec &u) { return is >> u.x >> u.y; }
  friend ostream &operator<<(ostream &os, vec &u) {
    return os << u.x << ' ' << u.y;
  }
};
struct line {
  double a, b, c;
  line(double na = 0, double nb = 0, double nc = 0) { a = na, b = nb, c = nc; }
  line(point p, point q) {
    double dx = q.x - p.x;
    double dy = q.y - p.y;
    if (fabs(dx) <= (1e-9)) {
      a = 1, b = 0, c = -p.x;
      return;
    }
    a = -dy / dx;
    b = 1.0;
    c = dy / dx * p.x - p.y;
  }
  line(point p, double m) {
    a = -m;
    b = 1.0;
    c = -(a * p.x + p.y);
  }
  pair<point, point> to_points() {
    point p, q;
    if (fabs(b) <= (1e-9))
      p.x = -c / a, q.x = p.x, p.y = 0, q.y = 1;
    else
      p.x = 0, q.x = 1, p.y = -(a * p.x + c), q.y = -(a * q.x + c);
    return make_pair(p, q);
  }
};
struct circle {
  double x, y, r;
  circle(point c = point(0, 0), double nr = 0) { x = c.x, y = c.y, r = nr; }
  int is_in(point p) {
    double dx = p.x - x, dy = p.y - y;
    double d = dx * dx + dy * dy, R = r * r;
    return (d < R - (1e-9)) ? 0 : (fabs(d - R) <= (1e-9)) ? 1 : 2;
  }
  double perimeter(double theta = 360) {
    theta = to_rad(theta);
    return theta * r;
  }
  double area(double theta = 360) {
    theta = to_rad(theta);
    return theta * r * r / 2;
  }
};
struct triangle {
  point A, B, C;
  double a, b, c;
  triangle(double na = 0, double nb = 0, double nc = 0) {
    a = na, b = nb, c = nc;
  }
  triangle(point nA, point nB, point nC) {
    A = nA, B = nB, C = nC;
    c = dist(A, B), a = dist(B, C), b = dist(C, A);
  }
  bool is_triangle() {
    return a + b > c + (1e-9) && b + c > a + (1e-9) && c + a > b + (1e-9);
  }
  double perimeter() { return a + b + c; }
  double area() {
    double s = perimeter() / 2;
    return sqrt(s * (s - a) * (s - b) * (s - c));
  }
};
double to_rad(double theta) { return theta * acos(-1.0) / 180; }
double to_deg(double theta) { return theta * 180 / acos(-1.0); }
double dist(point p, point q) { return hypot(p.x - q.x, p.y - q.y); }
point middle(point p, point q) {
  return point((p.x + q.x) / 2, (p.y + q.y) / 2);
}
point translate(point p, vec u) { return point(p.x + u.x, p.y + u.y); }
double norm_sq(vec u) { return u.x * u.x + u.y * u.y; }
double dot(vec u, vec v) { return u.x * v.x + u.y * v.y; }
double cross(vec u, vec v) { return u.x * v.y - u.y * v.x; }
bool are_parallel(line l, line d) {
  return fabs(l.a - d.a) <= (1e-9) && fabs(l.b - l.b) <= (1e-9);
}
bool are_same(line l, line d) {
  return are_parallel(l, d) && fabs(l.c - d.c) <= (1e-9);
}
double dist_to_line(point p, point a, point b) {
  return dist(p, projection(p, a, b));
}
bool ccw(point p, point q, point r) {
  return cross(vec(p, q), vec(p, r)) > 0 + (1e-9);
}
bool collinear(point p, point q, point r) {
  return fabs(cross(vec(p, q), vec(p, r))) <= (1e-9);
}
double angle(point a, point o, point b) {
  vec oa = vec(o, a), ob = vec(o, b);
  return acos(dot(oa, ob) / sqrt(norm_sq(oa) * norm_sq(ob)));
}
point rotate(point p, double theta, point q = point(0, 0)) {
  vec oq = vec(point(0, 0), q);
  p = translate(p, oq * -1);
  theta = to_rad(theta);
  double x = p.x * cos(theta) - p.y * sin(theta);
  double y = p.x * sin(theta) + p.y * cos(theta);
  p = point(x, y);
  p = translate(p, oq);
  return p;
}
point intersection(line l, line d) {
  point p;
  p.x = (d.b * l.c - l.b * d.c) / (d.a * l.b - l.a * d.b);
  if (fabs(l.b) > (1e-9))
    p.y = -(l.a * p.x + l.c);
  else
    p.y = -(d.a * p.x + d.c);
  return p;
}
point projection(point p, point a, point b) {
  vec ap = vec(a, p), ab = vec(a, b);
  double u = dot(ap, ab) / norm_sq(ab);
  return translate(a, ab * u);
}
double dist_to_segment(point p, point a, point b) {
  vec ap = vec(a, p), ab = vec(a, b);
  double u = dot(ap, ab) / norm_sq(ab);
  if (u < 0 - (1e-9)) return dist(p, a);
  if (u > 1 + (1e-9)) return dist(p, b);
  return dist_to_line(p, a, b);
}
point reflection(point p, point a, point b) {
  point c = projection(p, a, b);
  vec pc = vec(p, c);
  return translate(p, pc * 2);
}
line perpendicular(point p, point a, point b) {
  if (!collinear(p, a, b)) return line(p, projection(p, a, b));
  line l = line(a, b);
  if (fabs(l.b) <= (1e-9)) return line(p, point(p.x + 1, p.y));
  if (fabs(l.a) <= (1e-9)) return line(p, point(p.x, p.y + 1));
  return line(p, 1 / l.a);
}
line bisector(point a, point o, point b) {
  double ratio = dist(o, a) / dist(o, b);
  ratio /= ratio + 1;
  vec ab = vec(a, b);
  point c = translate(a, ab * ratio);
  return line(o, c);
}
circle find_circle(point p, point q, double r) {
  point m = middle(p, q);
  vec mp = vec(m, p);
  double mc = r * r - norm_sq(mp);
  if (mc < 0 - (1e-9)) return circle();
  mc = sqrt(mc);
  double u = mc / dist(m, p);
  point c = translate(m, mp * u);
  c = rotate(c, 90, m);
  return circle(c, r);
}
circle in_circle(triangle t) {
  double r = 2 * t.area() / t.perimeter();
  if (fabs(r) <= (1e-9)) return circle();
  line l = bisector(t.B, t.A, t.C);
  line d = bisector(t.C, t.B, t.A);
  point c = intersection(l, d);
  return circle(c, r);
}
circle circum_circle(triangle t) {
  double r = (t.a * t.b * t.c) / (4 * t.area());
  if (fabs(r) <= (1e-9)) return circle();
  line l = perpendicular(middle(t.A, t.B), t.A, t.B);
  line d = perpendicular(middle(t.A, t.C), t.A, t.C);
  point c = intersection(l, d);
  return circle(c, r);
}
point pivot;
double perimeter(vector<point> P) {
  int n = P.size();
  double ret = 0;
  for (int i = 0; i < n - 1; i++) ret += dist(P[i], P[i + 1]);
  return ret;
}
double area(vector<point> P) {
  int n = P.size();
  double ret = 0;
  double x1, x2, y1, y2;
  for (int i = 0; i < n - 1; i++) {
    x1 = P[i].x, x2 = P[i + 1].x;
    y1 = P[i].y, y2 = P[i + 1].y;
    ret += x1 * y2 - x2 * y1;
  }
  ret /= 2, ret = fabs(ret);
  return ret;
}
bool is_convex(vector<point> P) {
  int n = P.size();
  if (n <= 3) return false;
  bool turn = ccw(P[0], P[1], P[2]);
  for (int i = 1; i < n - 1; i++)
    if (ccw(P[i], P[i + 1], P[i + 2 != n ? i + 2 : 1]) != turn) return false;
  return true;
}
bool is_in(point p, vector<point> P) {
  int n = P.size();
  double sum = 0;
  for (int i = 0; i < n - 1; i++)
    if (ccw(P[i], p, P[i + 1]))
      sum += angle(P[i], p, P[i + 1]);
    else
      sum -= angle(P[i], p, P[i + 1]);
  sum = fabs(sum);
  return fabs(sum - 2 * acos(-1.0)) <= (1e-9);
}
vector<point> cut(vector<point> P, point a, point b) {
  int n = P.size();
  vector<point> ret;
  for (int i = 0; i < n; i++) {
    double left1 = cross(vec(a, b), vec(a, P[i]));
    double left2 = (i != n - 1) ? cross(vec(a, b), vec(a, P[i + 1])) : 0;
    if (left1 >= -(1e-9)) ret.push_back(P[i]);
    if (left1 * left2 < -(1e-9))
      ret.push_back(intersection(line(a, b), line(P[i], P[i + 1])));
  }
  if (!ret.empty() && ret.front() != ret.back()) ret.push_back(ret.front());
  return ret;
}
bool ch_cmp(point a, point b) {
  if (collinear(pivot, a, b)) return dist(pivot, a) < dist(pivot, b) - (1e-9);
  double dx1 = a.x - pivot.x, dy1 = a.y - pivot.y;
  double dx2 = b.x - pivot.x, dy2 = b.y - pivot.y;
  return atan2(dy1, dx1) < atan2(dy2, dx2) - (1e-9);
}
vector<point> convex_hull(vector<point> P) {
  int n = P.size();
  if (n <= 3) {
    if (n != 0 && P[0] != P[n - 1]) P.push_back(P[0]);
    return P;
  }
  int idx = 0;
  for (int i = 1; i < n; i++)
    if (P[idx].y > P[i].y + (1e-9) ||
        (fabs(P[idx].y - P[i].y) <= (1e-9) && P[idx].x < P[i].x - (1e-9)))
      idx = i;
  swap(P[0], P[idx]);
  pivot = P[0];
  sort(P.begin() + 1, P.end(), ch_cmp);
  vector<point> ch;
  ch.push_back(P[n - 1]), ch.push_back(P[0]), ch.push_back(P[1]);
  int i = 2;
  while (i < n) {
    int j = ch.size() - 1;
    if (ccw(ch[j - 1], ch[j], P[i]))
      ch.push_back(P[i]), i++;
    else
      ch.pop_back();
  }
  return ch;
}
void print(vector<point> P) {
  int n = P.size();
  cout << endl;
  for (int i = 0; i < n; i++) cout << P[i] << endl;
  cout << endl;
}
int main() {
  read_file();
  int x;
  while (cin >> x) {
    point p = point(0, 0);
    vector<point> P;
    P.push_back(p);
    vec u(1, 0);
    point q = translate(p, u * x);
    P.push_back(q);
    for (int i = 0; i < 5; i++) {
      cin >> x;
      u = vec(p, q);
      u = u * (1 / dist(p, q));
      p = q;
      q = translate(q, u * x);
      q = rotate(q, 60, p);
      P.push_back(q);
    }
    P.push_back(point(0, 0));
    double a = area(P);
    triangle t = triangle(1, 1, 1);
    double b = t.area();
    int ans = a / b + 1e-6;
    cout << ans << endl;
  }
}

### Prompt

Please provide a Cpp coded solution to the problem described below:

Gerald got a very curious hexagon for his birthday. The boy found out that all the angles of the hexagon are equal to <image>. Then he measured the length of its sides, and found that each of them is equal to an integer number of centimeters. There the properties of the hexagon ended and Gerald decided to draw on it.

He painted a few lines, parallel to the sides of the hexagon. The lines split the hexagon into regular triangles with sides of 1 centimeter. Now Gerald wonders how many triangles he has got. But there were so many of them that Gerald lost the track of his counting. Help the boy count the triangles.

Input

The first and the single line of the input contains 6 space-separated integers a1, a2, a3, a4, a5 and a6 (1 ≤ ai ≤ 1000) — the lengths of the sides of the hexagons in centimeters in the clockwise order. It is guaranteed that the hexagon with the indicated properties and the exactly such sides exists.

Output

Print a single integer — the number of triangles with the sides of one 1 centimeter, into which the hexagon is split.

Examples

Input

1 1 1 1 1 1


Output

6


Input

1 2 1 2 1 2


Output

13

Note

This is what Gerald's hexagon looks like in the first sample:

<image>

And that's what it looks like in the second sample:

<image>

### Response

```cpp
#include <bits/stdc++.h>
using namespace std;
void read_file(bool outToFile = true) {}
struct point;
struct vec;
struct line;
struct circle;
struct triangle;
double to_rad(double theta);
double to_deg(double theta);
double dist(point p, point q);
point middle(point p, point q);
point translate(point p, vec u);
double norm_sq(vec u);
double dot(vec u, vec v);
double cross(vec u, vec v);
bool are_parallel(line l, line d);
bool are_same(line l, line d);
double dist_to_line(point p, point a, point b);
bool ccw(point p, point q, point r);
bool collinear(point p, point q, point r);
double angle(point a, point o, point b);
point rotate(point p, double theta, point q);
point intersection(line l, line d);
point projection(point p, point a, point b);
double dist_to_segment(point p, point a, point b);
point reflection(point p, point a, point b);
line perpendicular(point p, point a, point b);
line bisector(point a, point o, point b);
circle find_circle(point p, point q, double r);
circle in_circle(triangle t);
circle circum_circle(triangle t);
double perimeter(vector<point> P);
double area(vector<point> P);
bool is_convex(vector<point> P);
bool is_in(point p, vector<point> P);
vector<point> cut(vector<point> P, point a, point b);
bool ch_cmp(point a, point b);
vector<point> convex_hull(vector<point> P);
struct point {
  double x, y;
  point(double nx = 0, double ny = 0) { x = nx, y = ny; }
  bool operator==(point p) {
    return fabs(x - p.x) <= (1e-9) && fabs(y - p.y) <= (1e-9);
  }
  bool operator!=(point p) {
    return fabs(x - p.x) > (1e-9) || fabs(y - p.y) > (1e-9);
  }
  bool operator<(point p) {
    if (fabs(x - p.x) > (1e-9)) return x < p.x - (1e-9);
    return y < p.y - (1e-9);
  }
  friend istream &operator>>(istream &is, point &p) { return is >> p.x >> p.y; }
  friend ostream &operator<<(ostream &os, point &p) {
    return os << p.x << ' ' << p.y;
  }
};
struct vec {
  double x, y;
  vec(double nx = 0, double ny = 0) { x = nx, y = ny; }
  vec(point p, point q) { x = q.x - p.x, y = q.y - p.y; }
  vec operator+(vec u) { return vec(x + u.x, y + u.y); }
  vec operator-(vec u) { return vec(x - u.x, y - u.y); }
  vec operator*(double k) { return vec(k * x, k * y); }
  friend istream &operator>>(istream &is, vec &u) { return is >> u.x >> u.y; }
  friend ostream &operator<<(ostream &os, vec &u) {
    return os << u.x << ' ' << u.y;
  }
};
struct line {
  double a, b, c;
  line(double na = 0, double nb = 0, double nc = 0) { a = na, b = nb, c = nc; }
  line(point p, point q) {
    double dx = q.x - p.x;
    double dy = q.y - p.y;
    if (fabs(dx) <= (1e-9)) {
      a = 1, b = 0, c = -p.x;
      return;
    }
    a = -dy / dx;
    b = 1.0;
    c = dy / dx * p.x - p.y;
  }
  line(point p, double m) {
    a = -m;
    b = 1.0;
    c = -(a * p.x + p.y);
  }
  pair<point, point> to_points() {
    point p, q;
    if (fabs(b) <= (1e-9))
      p.x = -c / a, q.x = p.x, p.y = 0, q.y = 1;
    else
      p.x = 0, q.x = 1, p.y = -(a * p.x + c), q.y = -(a * q.x + c);
    return make_pair(p, q);
  }
};
struct circle {
  double x, y, r;
  circle(point c = point(0, 0), double nr = 0) { x = c.x, y = c.y, r = nr; }
  int is_in(point p) {
    double dx = p.x - x, dy = p.y - y;
    double d = dx * dx + dy * dy, R = r * r;
    return (d < R - (1e-9)) ? 0 : (fabs(d - R) <= (1e-9)) ? 1 : 2;
  }
  double perimeter(double theta = 360) {
    theta = to_rad(theta);
    return theta * r;
  }
  double area(double theta = 360) {
    theta = to_rad(theta);
    return theta * r * r / 2;
  }
};
struct triangle {
  point A, B, C;
  double a, b, c;
  triangle(double na = 0, double nb = 0, double nc = 0) {
    a = na, b = nb, c = nc;
  }
  triangle(point nA, point nB, point nC) {
    A = nA, B = nB, C = nC;
    c = dist(A, B), a = dist(B, C), b = dist(C, A);
  }
  bool is_triangle() {
    return a + b > c + (1e-9) && b + c > a + (1e-9) && c + a > b + (1e-9);
  }
  double perimeter() { return a + b + c; }
  double area() {
    double s = perimeter() / 2;
    return sqrt(s * (s - a) * (s - b) * (s - c));
  }
};
double to_rad(double theta) { return theta * acos(-1.0) / 180; }
double to_deg(double theta) { return theta * 180 / acos(-1.0); }
double dist(point p, point q) { return hypot(p.x - q.x, p.y - q.y); }
point middle(point p, point q) {
  return point((p.x + q.x) / 2, (p.y + q.y) / 2);
}
point translate(point p, vec u) { return point(p.x + u.x, p.y + u.y); }
double norm_sq(vec u) { return u.x * u.x + u.y * u.y; }
double dot(vec u, vec v) { return u.x * v.x + u.y * v.y; }
double cross(vec u, vec v) { return u.x * v.y - u.y * v.x; }
bool are_parallel(line l, line d) {
  return fabs(l.a - d.a) <= (1e-9) && fabs(l.b - l.b) <= (1e-9);
}
bool are_same(line l, line d) {
  return are_parallel(l, d) && fabs(l.c - d.c) <= (1e-9);
}
double dist_to_line(point p, point a, point b) {
  return dist(p, projection(p, a, b));
}
bool ccw(point p, point q, point r) {
  return cross(vec(p, q), vec(p, r)) > 0 + (1e-9);
}
bool collinear(point p, point q, point r) {
  return fabs(cross(vec(p, q), vec(p, r))) <= (1e-9);
}
double angle(point a, point o, point b) {
  vec oa = vec(o, a), ob = vec(o, b);
  return acos(dot(oa, ob) / sqrt(norm_sq(oa) * norm_sq(ob)));
}
point rotate(point p, double theta, point q = point(0, 0)) {
  vec oq = vec(point(0, 0), q);
  p = translate(p, oq * -1);
  theta = to_rad(theta);
  double x = p.x * cos(theta) - p.y * sin(theta);
  double y = p.x * sin(theta) + p.y * cos(theta);
  p = point(x, y);
  p = translate(p, oq);
  return p;
}
point intersection(line l, line d) {
  point p;
  p.x = (d.b * l.c - l.b * d.c) / (d.a * l.b - l.a * d.b);
  if (fabs(l.b) > (1e-9))
    p.y = -(l.a * p.x + l.c);
  else
    p.y = -(d.a * p.x + d.c);
  return p;
}
point projection(point p, point a, point b) {
  vec ap = vec(a, p), ab = vec(a, b);
  double u = dot(ap, ab) / norm_sq(ab);
  return translate(a, ab * u);
}
double dist_to_segment(point p, point a, point b) {
  vec ap = vec(a, p), ab = vec(a, b);
  double u = dot(ap, ab) / norm_sq(ab);
  if (u < 0 - (1e-9)) return dist(p, a);
  if (u > 1 + (1e-9)) return dist(p, b);
  return dist_to_line(p, a, b);
}
point reflection(point p, point a, point b) {
  point c = projection(p, a, b);
  vec pc = vec(p, c);
  return translate(p, pc * 2);
}
line perpendicular(point p, point a, point b) {
  if (!collinear(p, a, b)) return line(p, projection(p, a, b));
  line l = line(a, b);
  if (fabs(l.b) <= (1e-9)) return line(p, point(p.x + 1, p.y));
  if (fabs(l.a) <= (1e-9)) return line(p, point(p.x, p.y + 1));
  return line(p, 1 / l.a);
}
line bisector(point a, point o, point b) {
  double ratio = dist(o, a) / dist(o, b);
  ratio /= ratio + 1;
  vec ab = vec(a, b);
  point c = translate(a, ab * ratio);
  return line(o, c);
}
circle find_circle(point p, point q, double r) {
  point m = middle(p, q);
  vec mp = vec(m, p);
  double mc = r * r - norm_sq(mp);
  if (mc < 0 - (1e-9)) return circle();
  mc = sqrt(mc);
  double u = mc / dist(m, p);
  point c = translate(m, mp * u);
  c = rotate(c, 90, m);
  return circle(c, r);
}
circle in_circle(triangle t) {
  double r = 2 * t.area() / t.perimeter();
  if (fabs(r) <= (1e-9)) return circle();
  line l = bisector(t.B, t.A, t.C);
  line d = bisector(t.C, t.B, t.A);
  point c = intersection(l, d);
  return circle(c, r);
}
circle circum_circle(triangle t) {
  double r = (t.a * t.b * t.c) / (4 * t.area());
  if (fabs(r) <= (1e-9)) return circle();
  line l = perpendicular(middle(t.A, t.B), t.A, t.B);
  line d = perpendicular(middle(t.A, t.C), t.A, t.C);
  point c = intersection(l, d);
  return circle(c, r);
}
point pivot;
double perimeter(vector<point> P) {
  int n = P.size();
  double ret = 0;
  for (int i = 0; i < n - 1; i++) ret += dist(P[i], P[i + 1]);
  return ret;
}
double area(vector<point> P) {
  int n = P.size();
  double ret = 0;
  double x1, x2, y1, y2;
  for (int i = 0; i < n - 1; i++) {
    x1 = P[i].x, x2 = P[i + 1].x;
    y1 = P[i].y, y2 = P[i + 1].y;
    ret += x1 * y2 - x2 * y1;
  }
  ret /= 2, ret = fabs(ret);
  return ret;
}
bool is_convex(vector<point> P) {
  int n = P.size();
  if (n <= 3) return false;
  bool turn = ccw(P[0], P[1], P[2]);
  for (int i = 1; i < n - 1; i++)
    if (ccw(P[i], P[i + 1], P[i + 2 != n ? i + 2 : 1]) != turn) return false;
  return true;
}
bool is_in(point p, vector<point> P) {
  int n = P.size();
  double sum = 0;
  for (int i = 0; i < n - 1; i++)
    if (ccw(P[i], p, P[i + 1]))
      sum += angle(P[i], p, P[i + 1]);
    else
      sum -= angle(P[i], p, P[i + 1]);
  sum = fabs(sum);
  return fabs(sum - 2 * acos(-1.0)) <= (1e-9);
}
vector<point> cut(vector<point> P, point a, point b) {
  int n = P.size();
  vector<point> ret;
  for (int i = 0; i < n; i++) {
    double left1 = cross(vec(a, b), vec(a, P[i]));
    double left2 = (i != n - 1) ? cross(vec(a, b), vec(a, P[i + 1])) : 0;
    if (left1 >= -(1e-9)) ret.push_back(P[i]);
    if (left1 * left2 < -(1e-9))
      ret.push_back(intersection(line(a, b), line(P[i], P[i + 1])));
  }
  if (!ret.empty() && ret.front() != ret.back()) ret.push_back(ret.front());
  return ret;
}
bool ch_cmp(point a, point b) {
  if (collinear(pivot, a, b)) return dist(pivot, a) < dist(pivot, b) - (1e-9);
  double dx1 = a.x - pivot.x, dy1 = a.y - pivot.y;
  double dx2 = b.x - pivot.x, dy2 = b.y - pivot.y;
  return atan2(dy1, dx1) < atan2(dy2, dx2) - (1e-9);
}
vector<point> convex_hull(vector<point> P) {
  int n = P.size();
  if (n <= 3) {
    if (n != 0 && P[0] != P[n - 1]) P.push_back(P[0]);
    return P;
  }
  int idx = 0;
  for (int i = 1; i < n; i++)
    if (P[idx].y > P[i].y + (1e-9) ||
        (fabs(P[idx].y - P[i].y) <= (1e-9) && P[idx].x < P[i].x - (1e-9)))
      idx = i;
  swap(P[0], P[idx]);
  pivot = P[0];
  sort(P.begin() + 1, P.end(), ch_cmp);
  vector<point> ch;
  ch.push_back(P[n - 1]), ch.push_back(P[0]), ch.push_back(P[1]);
  int i = 2;
  while (i < n) {
    int j = ch.size() - 1;
    if (ccw(ch[j - 1], ch[j], P[i]))
      ch.push_back(P[i]), i++;
    else
      ch.pop_back();
  }
  return ch;
}
void print(vector<point> P) {
  int n = P.size();
  cout << endl;
  for (int i = 0; i < n; i++) cout << P[i] << endl;
  cout << endl;
}
int main() {
  read_file();
  int x;
  while (cin >> x) {
    point p = point(0, 0);
    vector<point> P;
    P.push_back(p);
    vec u(1, 0);
    point q = translate(p, u * x);
    P.push_back(q);
    for (int i = 0; i < 5; i++) {
      cin >> x;
      u = vec(p, q);
      u = u * (1 / dist(p, q));
      p = q;
      q = translate(q, u * x);
      q = rotate(q, 60, p);
      P.push_back(q);
    }
    P.push_back(point(0, 0));
    double a = area(P);
    triangle t = triangle(1, 1, 1);
    double b = t.area();
    int ans = a / b + 1e-6;
    cout << ans << endl;
  }
}

```