
(FPCore (a b) :precision binary64 (- (* (* (* a a) b) b)))
double code(double a, double b) {
return -(((a * a) * b) * b);
}
real(8) function code(a, b)
real(8), intent (in) :: a
real(8), intent (in) :: b
code = -(((a * a) * b) * b)
end function
public static double code(double a, double b) {
return -(((a * a) * b) * b);
}
def code(a, b): return -(((a * a) * b) * b)
function code(a, b) return Float64(-Float64(Float64(Float64(a * a) * b) * b)) end
function tmp = code(a, b) tmp = -(((a * a) * b) * b); end
code[a_, b_] := (-N[(N[(N[(a * a), $MachinePrecision] * b), $MachinePrecision] * b), $MachinePrecision])
\begin{array}{l}
\\
-\left(\left(a \cdot a\right) \cdot b\right) \cdot b
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 10 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (a b) :precision binary64 (- (* (* (* a a) b) b)))
double code(double a, double b) {
return -(((a * a) * b) * b);
}
real(8) function code(a, b)
real(8), intent (in) :: a
real(8), intent (in) :: b
code = -(((a * a) * b) * b)
end function
public static double code(double a, double b) {
return -(((a * a) * b) * b);
}
def code(a, b): return -(((a * a) * b) * b)
function code(a, b) return Float64(-Float64(Float64(Float64(a * a) * b) * b)) end
function tmp = code(a, b) tmp = -(((a * a) * b) * b); end
code[a_, b_] := (-N[(N[(N[(a * a), $MachinePrecision] * b), $MachinePrecision] * b), $MachinePrecision])
\begin{array}{l}
\\
-\left(\left(a \cdot a\right) \cdot b\right) \cdot b
\end{array}
NOTE: a should be positive before calling this function NOTE: a and b should be sorted in increasing order before calling this function. (FPCore (a b) :precision binary64 (* (/ a (/ -1.0 b)) (* a b)))
a = abs(a);
assert(a < b);
double code(double a, double b) {
return (a / (-1.0 / b)) * (a * b);
}
NOTE: a should be positive before calling this function
NOTE: a and b should be sorted in increasing order before calling this function.
real(8) function code(a, b)
real(8), intent (in) :: a
real(8), intent (in) :: b
code = (a / ((-1.0d0) / b)) * (a * b)
end function
a = Math.abs(a);
assert a < b;
public static double code(double a, double b) {
return (a / (-1.0 / b)) * (a * b);
}
a = abs(a) [a, b] = sort([a, b]) def code(a, b): return (a / (-1.0 / b)) * (a * b)
a = abs(a) a, b = sort([a, b]) function code(a, b) return Float64(Float64(a / Float64(-1.0 / b)) * Float64(a * b)) end
a = abs(a)
a, b = num2cell(sort([a, b])){:}
function tmp = code(a, b)
tmp = (a / (-1.0 / b)) * (a * b);
end
NOTE: a should be positive before calling this function NOTE: a and b should be sorted in increasing order before calling this function. code[a_, b_] := N[(N[(a / N[(-1.0 / b), $MachinePrecision]), $MachinePrecision] * N[(a * b), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
a = |a|\\
[a, b] = \mathsf{sort}([a, b])\\
\\
\frac{a}{\frac{-1}{b}} \cdot \left(a \cdot b\right)
\end{array}
Initial program 81.1%
distribute-rgt-neg-in81.1%
associate-*l*92.7%
Simplified92.7%
add-sqr-sqrt_binary6452.9%
Applied rewrite-once52.9%
rem-square-sqrt92.7%
associate-*r*81.1%
associate-*l*73.0%
/-rgt-identity73.0%
associate-/l*73.0%
associate-*l/79.5%
Applied egg-rr79.5%
associate-/l*79.5%
div-inv79.5%
associate-*r/79.5%
div-inv79.5%
*-commutative79.5%
times-frac91.9%
times-frac99.6%
associate-/r*99.6%
clear-num99.7%
/-rgt-identity99.7%
neg-mul-199.7%
associate-/r*99.7%
metadata-eval99.7%
Applied egg-rr99.7%
Final simplification99.7%
NOTE: a should be positive before calling this function NOTE: a and b should be sorted in increasing order before calling this function. (FPCore (a b) :precision binary64 (if (<= b 1.35e+154) (* a (* a (- (* b b)))) (* b (* b (* a (- a))))))
a = abs(a);
assert(a < b);
double code(double a, double b) {
double tmp;
if (b <= 1.35e+154) {
tmp = a * (a * -(b * b));
} else {
tmp = b * (b * (a * -a));
}
return tmp;
}
NOTE: a should be positive before calling this function
NOTE: a and b should be sorted in increasing order before calling this function.
real(8) function code(a, b)
real(8), intent (in) :: a
real(8), intent (in) :: b
real(8) :: tmp
if (b <= 1.35d+154) then
tmp = a * (a * -(b * b))
else
tmp = b * (b * (a * -a))
end if
code = tmp
end function
a = Math.abs(a);
assert a < b;
public static double code(double a, double b) {
double tmp;
if (b <= 1.35e+154) {
tmp = a * (a * -(b * b));
} else {
tmp = b * (b * (a * -a));
}
return tmp;
}
a = abs(a) [a, b] = sort([a, b]) def code(a, b): tmp = 0 if b <= 1.35e+154: tmp = a * (a * -(b * b)) else: tmp = b * (b * (a * -a)) return tmp
a = abs(a) a, b = sort([a, b]) function code(a, b) tmp = 0.0 if (b <= 1.35e+154) tmp = Float64(a * Float64(a * Float64(-Float64(b * b)))); else tmp = Float64(b * Float64(b * Float64(a * Float64(-a)))); end return tmp end
a = abs(a)
a, b = num2cell(sort([a, b])){:}
function tmp_2 = code(a, b)
tmp = 0.0;
if (b <= 1.35e+154)
tmp = a * (a * -(b * b));
else
tmp = b * (b * (a * -a));
end
tmp_2 = tmp;
end
NOTE: a should be positive before calling this function NOTE: a and b should be sorted in increasing order before calling this function. code[a_, b_] := If[LessEqual[b, 1.35e+154], N[(a * N[(a * (-N[(b * b), $MachinePrecision])), $MachinePrecision]), $MachinePrecision], N[(b * N[(b * N[(a * (-a)), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
a = |a|\\
[a, b] = \mathsf{sort}([a, b])\\
\\
\begin{array}{l}
\mathbf{if}\;b \leq 1.35 \cdot 10^{+154}:\\
\;\;\;\;a \cdot \left(a \cdot \left(-b \cdot b\right)\right)\\
\mathbf{else}:\\
\;\;\;\;b \cdot \left(b \cdot \left(a \cdot \left(-a\right)\right)\right)\\
\end{array}
\end{array}
if b < 1.35000000000000003e154Initial program 82.8%
associate-*l*76.9%
distribute-rgt-neg-in76.9%
associate-*r*84.4%
Simplified84.4%
if 1.35000000000000003e154 < b Initial program 71.2%
Final simplification82.5%
NOTE: a should be positive before calling this function NOTE: a and b should be sorted in increasing order before calling this function. (FPCore (a b) :precision binary64 (if (<= b 1.35e+154) (* a (* a (- (* b b)))) (* b (* (* a b) (- a)))))
a = abs(a);
assert(a < b);
double code(double a, double b) {
double tmp;
if (b <= 1.35e+154) {
tmp = a * (a * -(b * b));
} else {
tmp = b * ((a * b) * -a);
}
return tmp;
}
NOTE: a should be positive before calling this function
NOTE: a and b should be sorted in increasing order before calling this function.
real(8) function code(a, b)
real(8), intent (in) :: a
real(8), intent (in) :: b
real(8) :: tmp
if (b <= 1.35d+154) then
tmp = a * (a * -(b * b))
else
tmp = b * ((a * b) * -a)
end if
code = tmp
end function
a = Math.abs(a);
assert a < b;
public static double code(double a, double b) {
double tmp;
if (b <= 1.35e+154) {
tmp = a * (a * -(b * b));
} else {
tmp = b * ((a * b) * -a);
}
return tmp;
}
a = abs(a) [a, b] = sort([a, b]) def code(a, b): tmp = 0 if b <= 1.35e+154: tmp = a * (a * -(b * b)) else: tmp = b * ((a * b) * -a) return tmp
a = abs(a) a, b = sort([a, b]) function code(a, b) tmp = 0.0 if (b <= 1.35e+154) tmp = Float64(a * Float64(a * Float64(-Float64(b * b)))); else tmp = Float64(b * Float64(Float64(a * b) * Float64(-a))); end return tmp end
a = abs(a)
a, b = num2cell(sort([a, b])){:}
function tmp_2 = code(a, b)
tmp = 0.0;
if (b <= 1.35e+154)
tmp = a * (a * -(b * b));
else
tmp = b * ((a * b) * -a);
end
tmp_2 = tmp;
end
NOTE: a should be positive before calling this function NOTE: a and b should be sorted in increasing order before calling this function. code[a_, b_] := If[LessEqual[b, 1.35e+154], N[(a * N[(a * (-N[(b * b), $MachinePrecision])), $MachinePrecision]), $MachinePrecision], N[(b * N[(N[(a * b), $MachinePrecision] * (-a)), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
a = |a|\\
[a, b] = \mathsf{sort}([a, b])\\
\\
\begin{array}{l}
\mathbf{if}\;b \leq 1.35 \cdot 10^{+154}:\\
\;\;\;\;a \cdot \left(a \cdot \left(-b \cdot b\right)\right)\\
\mathbf{else}:\\
\;\;\;\;b \cdot \left(\left(a \cdot b\right) \cdot \left(-a\right)\right)\\
\end{array}
\end{array}
if b < 1.35000000000000003e154Initial program 82.8%
associate-*l*76.9%
distribute-rgt-neg-in76.9%
associate-*r*84.4%
Simplified84.4%
if 1.35000000000000003e154 < b Initial program 71.2%
distribute-rgt-neg-in71.2%
associate-*l*92.0%
Simplified92.0%
Final simplification85.5%
NOTE: a should be positive before calling this function NOTE: a and b should be sorted in increasing order before calling this function. (FPCore (a b) :precision binary64 (* b (* b (* a (- a)))))
a = abs(a);
assert(a < b);
double code(double a, double b) {
return b * (b * (a * -a));
}
NOTE: a should be positive before calling this function
NOTE: a and b should be sorted in increasing order before calling this function.
real(8) function code(a, b)
real(8), intent (in) :: a
real(8), intent (in) :: b
code = b * (b * (a * -a))
end function
a = Math.abs(a);
assert a < b;
public static double code(double a, double b) {
return b * (b * (a * -a));
}
a = abs(a) [a, b] = sort([a, b]) def code(a, b): return b * (b * (a * -a))
a = abs(a) a, b = sort([a, b]) function code(a, b) return Float64(b * Float64(b * Float64(a * Float64(-a)))) end
a = abs(a)
a, b = num2cell(sort([a, b])){:}
function tmp = code(a, b)
tmp = b * (b * (a * -a));
end
NOTE: a should be positive before calling this function NOTE: a and b should be sorted in increasing order before calling this function. code[a_, b_] := N[(b * N[(b * N[(a * (-a)), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
a = |a|\\
[a, b] = \mathsf{sort}([a, b])\\
\\
b \cdot \left(b \cdot \left(a \cdot \left(-a\right)\right)\right)
\end{array}
Initial program 81.1%
Final simplification81.1%
NOTE: a should be positive before calling this function NOTE: a and b should be sorted in increasing order before calling this function. (FPCore (a b) :precision binary64 (- (* (* a b) (* a b))))
a = abs(a);
assert(a < b);
double code(double a, double b) {
return -((a * b) * (a * b));
}
NOTE: a should be positive before calling this function
NOTE: a and b should be sorted in increasing order before calling this function.
real(8) function code(a, b)
real(8), intent (in) :: a
real(8), intent (in) :: b
code = -((a * b) * (a * b))
end function
a = Math.abs(a);
assert a < b;
public static double code(double a, double b) {
return -((a * b) * (a * b));
}
a = abs(a) [a, b] = sort([a, b]) def code(a, b): return -((a * b) * (a * b))
a = abs(a) a, b = sort([a, b]) function code(a, b) return Float64(-Float64(Float64(a * b) * Float64(a * b))) end
a = abs(a)
a, b = num2cell(sort([a, b])){:}
function tmp = code(a, b)
tmp = -((a * b) * (a * b));
end
NOTE: a should be positive before calling this function NOTE: a and b should be sorted in increasing order before calling this function. code[a_, b_] := (-N[(N[(a * b), $MachinePrecision] * N[(a * b), $MachinePrecision]), $MachinePrecision])
\begin{array}{l}
a = |a|\\
[a, b] = \mathsf{sort}([a, b])\\
\\
-\left(a \cdot b\right) \cdot \left(a \cdot b\right)
\end{array}
Initial program 81.1%
distribute-rgt-neg-in81.1%
associate-*l*92.7%
Simplified92.7%
add-sqr-sqrt_binary6452.9%
Applied rewrite-once52.9%
rem-square-sqrt92.7%
associate-*r*81.1%
associate-*l*73.0%
/-rgt-identity73.0%
associate-/l*73.0%
associate-*l/79.5%
Applied egg-rr79.5%
clear-num79.5%
associate-/r/79.5%
remove-double-div79.5%
distribute-rgt-neg-out79.5%
distribute-rgt-neg-out79.5%
distribute-lft-neg-out79.5%
associate-*l*73.0%
associate-*r*81.1%
*-commutative81.1%
*-commutative81.1%
associate-*l*92.7%
associate-*r*99.7%
Applied egg-rr99.7%
Final simplification99.7%
NOTE: a should be positive before calling this function NOTE: a and b should be sorted in increasing order before calling this function. (FPCore (a b) :precision binary64 (if (<= b 8e-7) 0.0 (* a (- a))))
a = abs(a);
assert(a < b);
double code(double a, double b) {
double tmp;
if (b <= 8e-7) {
tmp = 0.0;
} else {
tmp = a * -a;
}
return tmp;
}
NOTE: a should be positive before calling this function
NOTE: a and b should be sorted in increasing order before calling this function.
real(8) function code(a, b)
real(8), intent (in) :: a
real(8), intent (in) :: b
real(8) :: tmp
if (b <= 8d-7) then
tmp = 0.0d0
else
tmp = a * -a
end if
code = tmp
end function
a = Math.abs(a);
assert a < b;
public static double code(double a, double b) {
double tmp;
if (b <= 8e-7) {
tmp = 0.0;
} else {
tmp = a * -a;
}
return tmp;
}
a = abs(a) [a, b] = sort([a, b]) def code(a, b): tmp = 0 if b <= 8e-7: tmp = 0.0 else: tmp = a * -a return tmp
a = abs(a) a, b = sort([a, b]) function code(a, b) tmp = 0.0 if (b <= 8e-7) tmp = 0.0; else tmp = Float64(a * Float64(-a)); end return tmp end
a = abs(a)
a, b = num2cell(sort([a, b])){:}
function tmp_2 = code(a, b)
tmp = 0.0;
if (b <= 8e-7)
tmp = 0.0;
else
tmp = a * -a;
end
tmp_2 = tmp;
end
NOTE: a should be positive before calling this function NOTE: a and b should be sorted in increasing order before calling this function. code[a_, b_] := If[LessEqual[b, 8e-7], 0.0, N[(a * (-a)), $MachinePrecision]]
\begin{array}{l}
a = |a|\\
[a, b] = \mathsf{sort}([a, b])\\
\\
\begin{array}{l}
\mathbf{if}\;b \leq 8 \cdot 10^{-7}:\\
\;\;\;\;0\\
\mathbf{else}:\\
\;\;\;\;a \cdot \left(-a\right)\\
\end{array}
\end{array}
if b < 7.9999999999999996e-7Initial program 82.1%
distribute-rgt-neg-in82.1%
associate-*l*92.9%
Simplified92.9%
add-sqr-sqrt_binary6440.4%
Applied rewrite-once40.4%
rem-square-sqrt92.9%
associate-*r*82.1%
associate-*l*75.4%
/-rgt-identity75.4%
associate-/l*75.4%
associate-*l/82.3%
Applied egg-rr82.3%
associate-/l*82.4%
div-inv82.3%
associate-*r/82.4%
div-inv82.4%
*-commutative82.4%
times-frac91.9%
times-frac99.6%
associate-/r*99.7%
clear-num99.7%
/-rgt-identity99.7%
neg-mul-199.7%
associate-/r*99.7%
metadata-eval99.7%
Applied egg-rr99.7%
Applied egg-rr39.0%
if 7.9999999999999996e-7 < b Initial program 78.2%
associate-*l*65.5%
distribute-rgt-neg-in65.5%
associate-*r*70.6%
Simplified70.6%
Applied egg-rr34.9%
+-rgt-identity34.9%
Simplified34.9%
Final simplification38.0%
NOTE: a should be positive before calling this function NOTE: a and b should be sorted in increasing order before calling this function. (FPCore (a b) :precision binary64 (* (* a b) (- a)))
a = abs(a);
assert(a < b);
double code(double a, double b) {
return (a * b) * -a;
}
NOTE: a should be positive before calling this function
NOTE: a and b should be sorted in increasing order before calling this function.
real(8) function code(a, b)
real(8), intent (in) :: a
real(8), intent (in) :: b
code = (a * b) * -a
end function
a = Math.abs(a);
assert a < b;
public static double code(double a, double b) {
return (a * b) * -a;
}
a = abs(a) [a, b] = sort([a, b]) def code(a, b): return (a * b) * -a
a = abs(a) a, b = sort([a, b]) function code(a, b) return Float64(Float64(a * b) * Float64(-a)) end
a = abs(a)
a, b = num2cell(sort([a, b])){:}
function tmp = code(a, b)
tmp = (a * b) * -a;
end
NOTE: a should be positive before calling this function NOTE: a and b should be sorted in increasing order before calling this function. code[a_, b_] := N[(N[(a * b), $MachinePrecision] * (-a)), $MachinePrecision]
\begin{array}{l}
a = |a|\\
[a, b] = \mathsf{sort}([a, b])\\
\\
\left(a \cdot b\right) \cdot \left(-a\right)
\end{array}
Initial program 81.1%
distribute-rgt-neg-in81.1%
associate-*l*92.7%
Simplified92.7%
Applied egg-rr31.6%
+-rgt-identity31.6%
Simplified31.6%
Taylor expanded in a around 0 31.6%
mul-1-neg31.6%
unpow231.6%
distribute-rgt-neg-out31.6%
associate-*l*31.6%
Simplified31.6%
Final simplification31.6%
NOTE: a should be positive before calling this function NOTE: a and b should be sorted in increasing order before calling this function. (FPCore (a b) :precision binary64 -9.0)
a = abs(a);
assert(a < b);
double code(double a, double b) {
return -9.0;
}
NOTE: a should be positive before calling this function
NOTE: a and b should be sorted in increasing order before calling this function.
real(8) function code(a, b)
real(8), intent (in) :: a
real(8), intent (in) :: b
code = -9.0d0
end function
a = Math.abs(a);
assert a < b;
public static double code(double a, double b) {
return -9.0;
}
a = abs(a) [a, b] = sort([a, b]) def code(a, b): return -9.0
a = abs(a) a, b = sort([a, b]) function code(a, b) return -9.0 end
a = abs(a)
a, b = num2cell(sort([a, b])){:}
function tmp = code(a, b)
tmp = -9.0;
end
NOTE: a should be positive before calling this function NOTE: a and b should be sorted in increasing order before calling this function. code[a_, b_] := -9.0
\begin{array}{l}
a = |a|\\
[a, b] = \mathsf{sort}([a, b])\\
\\
-9
\end{array}
Initial program 81.1%
distribute-rgt-neg-in81.1%
associate-*l*92.7%
Simplified92.7%
add-sqr-sqrt_binary6452.9%
Applied rewrite-once52.9%
rem-square-sqrt92.7%
associate-*r*81.1%
associate-*l*73.0%
/-rgt-identity73.0%
associate-/l*73.0%
associate-*l/79.5%
Applied egg-rr79.5%
associate-/l*79.5%
div-inv79.5%
associate-*r/79.5%
div-inv79.5%
*-commutative79.5%
times-frac91.9%
times-frac99.6%
associate-/r*99.6%
clear-num99.7%
/-rgt-identity99.7%
neg-mul-199.7%
associate-/r*99.7%
metadata-eval99.7%
Applied egg-rr99.7%
Applied egg-rr4.0%
Final simplification4.0%
NOTE: a should be positive before calling this function NOTE: a and b should be sorted in increasing order before calling this function. (FPCore (a b) :precision binary64 -0.125)
a = abs(a);
assert(a < b);
double code(double a, double b) {
return -0.125;
}
NOTE: a should be positive before calling this function
NOTE: a and b should be sorted in increasing order before calling this function.
real(8) function code(a, b)
real(8), intent (in) :: a
real(8), intent (in) :: b
code = -0.125d0
end function
a = Math.abs(a);
assert a < b;
public static double code(double a, double b) {
return -0.125;
}
a = abs(a) [a, b] = sort([a, b]) def code(a, b): return -0.125
a = abs(a) a, b = sort([a, b]) function code(a, b) return -0.125 end
a = abs(a)
a, b = num2cell(sort([a, b])){:}
function tmp = code(a, b)
tmp = -0.125;
end
NOTE: a should be positive before calling this function NOTE: a and b should be sorted in increasing order before calling this function. code[a_, b_] := -0.125
\begin{array}{l}
a = |a|\\
[a, b] = \mathsf{sort}([a, b])\\
\\
-0.125
\end{array}
Initial program 81.1%
distribute-rgt-neg-in81.1%
associate-*l*92.7%
Simplified92.7%
add-sqr-sqrt_binary6452.9%
Applied rewrite-once52.9%
rem-square-sqrt92.7%
associate-*r*81.1%
associate-*l*73.0%
/-rgt-identity73.0%
associate-/l*73.0%
associate-*l/79.5%
Applied egg-rr79.5%
associate-/l*79.5%
div-inv79.5%
associate-*r/79.5%
div-inv79.5%
*-commutative79.5%
times-frac91.9%
times-frac99.6%
associate-/r*99.6%
clear-num99.7%
/-rgt-identity99.7%
neg-mul-199.7%
associate-/r*99.7%
metadata-eval99.7%
Applied egg-rr99.7%
Applied egg-rr4.0%
Final simplification4.0%
NOTE: a should be positive before calling this function NOTE: a and b should be sorted in increasing order before calling this function. (FPCore (a b) :precision binary64 0.0)
a = abs(a);
assert(a < b);
double code(double a, double b) {
return 0.0;
}
NOTE: a should be positive before calling this function
NOTE: a and b should be sorted in increasing order before calling this function.
real(8) function code(a, b)
real(8), intent (in) :: a
real(8), intent (in) :: b
code = 0.0d0
end function
a = Math.abs(a);
assert a < b;
public static double code(double a, double b) {
return 0.0;
}
a = abs(a) [a, b] = sort([a, b]) def code(a, b): return 0.0
a = abs(a) a, b = sort([a, b]) function code(a, b) return 0.0 end
a = abs(a)
a, b = num2cell(sort([a, b])){:}
function tmp = code(a, b)
tmp = 0.0;
end
NOTE: a should be positive before calling this function NOTE: a and b should be sorted in increasing order before calling this function. code[a_, b_] := 0.0
\begin{array}{l}
a = |a|\\
[a, b] = \mathsf{sort}([a, b])\\
\\
0
\end{array}
Initial program 81.1%
distribute-rgt-neg-in81.1%
associate-*l*92.7%
Simplified92.7%
add-sqr-sqrt_binary6452.9%
Applied rewrite-once52.9%
rem-square-sqrt92.7%
associate-*r*81.1%
associate-*l*73.0%
/-rgt-identity73.0%
associate-/l*73.0%
associate-*l/79.5%
Applied egg-rr79.5%
associate-/l*79.5%
div-inv79.5%
associate-*r/79.5%
div-inv79.5%
*-commutative79.5%
times-frac91.9%
times-frac99.6%
associate-/r*99.6%
clear-num99.7%
/-rgt-identity99.7%
neg-mul-199.7%
associate-/r*99.7%
metadata-eval99.7%
Applied egg-rr99.7%
Applied egg-rr33.2%
Final simplification33.2%
herbie shell --seed 2023297
(FPCore (a b)
:name "ab-angle->ABCF D"
:precision binary64
(- (* (* (* a a) b) b)))