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v/examples/wasm/functions.v

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// `pub` functions will be exported.
//
// ```
// v -b wasm -no-builtin functions.v
// wasmer functions.wasm -i main.powi <a> <b>
// wasmer functions.wasm -i main.gcd <a> <b>
// ```
pub fn gcd(a_ i64, b_ i64) i64 {
mut a := a_
mut b := b_
if a < 0 {
a = -a
}
if b < 0 {
b = -b
}
for b != 0 {
a %= b
if a == 0 {
return b
}
b %= a
}
return a
}
pub fn powi(a i64, b i64) i64 {
mut b_ := b
mut p := a
mut v := i64(1)
if b_ < 0 { // exponent < 0
if a == 0 {
return -1 // division by 0
}
return if a * a != 1 {
0
} else {
if (b_ & 1) > 0 {
a
} else {
1
}
}
}
for b_ > 0 {
if b_ & 1 > 0 {
v *= p
}
p *= p
b_ >>= 1
}
return v
}