题解 | 进制转换

package main

import (
	"bufio"
	"fmt"
	"os"
)

func main() {
    reader := bufio.NewScanner(os.Stdin)
    reader.Scan()
    input := reader.Text()
    input = input[2:]
    length := len(input)
    res := 0

    for i := 0; i < length; i ++ {
        char := input[i]
        val := 0
        if char >= '0' && char <= '9' {
            val = int(char - '0')
        } else if char >= 'A' && char <= 'F' {
            val = int(char - 'A' + 10)
        }
        res = res*16 + val
    }
    fmt.Println(res)
   
    
}

进位相加，秦九昭算法