找出big.Int的平方根

Question

I am required to use big.Ints for my project because the numbers I am working with exceed the int64 limit.

With regular ints, you can square it using:

math.Sqrt(value)

But I can't work out how to do this, but with big.Ints.

Any help would be appreciated greatly,

Thanks

Answer 1

Use https://golang.org/pkg/math/big/#Int.Sqrt given in big.int interface

package main

import (
    "fmt"
    "math/big"
)

func main() {
    var Str = `10000000000000000000000000000000000000000000000000000`
    bigInt := &big.Int{}
    value, _ := bigInt.SetString(Str, 10)
    sqrt := bigInt.Sqrt(value)
    fmt.Println(sqrt)
}

Output:

100000000000000000000000000