golang 我正在努力学习去讨厌自己

Posted 2021-05-24

package main

import (
	"fmt"
	"strconv"
)

func main() {
	fmt.Println(sum(3,255))
}

func sum(one, two uint8) (out uint16) {
	var outBits [8]byte
	sum, carry := halfAdder( getBit(one, 0), getBit(two, 0) )
	if sum {
		outBits[0] = '1'
	} else {
		outBits[0] = '0'
	}
	for i := 7; i >= 0; i-- {
		sum, carry = fullAdder( getBit(one, i), getBit(two, i), carry )
		if sum {
			outBits[i] = '1'
		} else {
			outBits[i] = '0'
		}
	}
	var carryChar string
	if carry {
		carryChar = "1"
	} else {
		carryChar = "0"
	}
	out64,_ := strconv.ParseUint(carryChar + string(outBits[:8]), 2, 16)
	out = uint16(out64)
	
	return
}

func halfAdder(one bool, two bool) (sum bool, carry bool) {
	sum = one != two
	carry = one && two
	return
}

func fullAdder(one bool, two bool, carryIn bool) (sum bool, carryOut bool) {
	xor := one != two
	sum = xor != carryIn

	and1 := one && two
	and2 := xor && carryIn
	carryOut = and1 || and2
	return
}

func getBit(value uint8, pos int) bool {
	bin := strconv.FormatUint(uint64(value), 2)
	binLen := len(bin)
	var bin8 [8]byte
	for i := 0; i < (8-binLen); i++ {
		bin8[i] = '0'
	}
	for i := (8-binLen); i < 8; i++ {
		bin8[i] = bin[i-(8-binLen)]
	}
	return bin8[pos] == 49
}

golang 去并发测试（我学习去）

package main

import (
    "fmt"
    "time"
)

func main() {
    fmt.Println("Concurrency test")

    concurrency := 5
    workers := make(chan bool, concurrency)

    // Ensure each worker is set to true (ready)
    for i := 0; i < cap(workers); i++ {
        select {
            default:
                workers <- true
        }
    }

    // i is purely for output reasons
    for i := 0; ; i++ {
        select {
            case <-workers:
                output := make(chan string)

                go func(w chan bool) {
                    defer func() {
                        w <- true
                    }()

                    output <- fmt.Sprintf("request %d", i)
                    time.Sleep(1000 * time.Millisecond)
                }(workers)

                fmt.Println(<-output)
        }
    }
}