57 lines
1.2 KiB
Go
57 lines
1.2 KiB
Go
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package hexadecimal
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import (
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"errors"
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"fmt"
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"math/big"
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"strings"
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)
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func ParseHex(in string) (int64, error) {
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return convertNumStringBase(in, int64(16))
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}
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func HandleErrors(in []string) []string {
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var ret []string
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for i := range in {
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_, err := convertNumStringBase(in[i], 16)
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ret = append(ret, err.Error())
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}
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return ret
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}
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// convertNumStringBase takes a numeric string and the base of that string
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// and returns an int64 of the decimal representation
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func convertNumStringBase(in string, oldBase int64) (int64, error) {
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if in == "" {
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return 0, errors.New("syntax")
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}
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in = strings.ToLower(in)
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base := big.NewInt(oldBase)
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var sum big.Int
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for i := range in {
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var x *big.Int
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if in[i] >= '0' && in[i] <= '9' {
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x = big.NewInt(int64(in[i] - '0'))
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} else if in[i] >= 'a' && in[i] <= 'z' {
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x = big.NewInt(int64(in[i]-'a') + 10)
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}
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fmt.Println("Comparing Converted Value ", x, "<", oldBase)
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if x.Int64() > oldBase {
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return 0, errors.New("syntax")
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}
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pow := big.NewInt(int64(len(in) - i - 1))
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var n big.Int
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n.Exp(base, pow, nil)
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n.Mul(x, &n)
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sum.Add(&sum, &n)
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if sum.Int64() < 0 {
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return 0, errors.New("Integer Overflow")
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}
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}
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return sum.Int64(), nil
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}
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