Mens et manus

如果輸入"X 3",輸出 3 = 3

如果輸入"X 23",輸出 23 = 20 + 3

如果輸入"X 234",輸出 233 = 199 + 30 + 4

如果輸入"X 2345",輸出 2344 = 1999 + 300 + 40 + 4

這個鬼問題不知道是不是浮點數...

/*8/22寫下的程式碼*/

String readStr = String(100);
String str1 = String(3);
String str2 = String(10);

int pos = 0;
int ind1 = 0;
int ind2 = 0;

//#include <Servo.h>
//Servo myservo;  // create servo object to control a servo

void setup()
{
  Serial.begin(9600);
}

void loop()
{
  //expect a string like wer,qwe rty,123 456,hyre kjhg,
  while( Serial.available() )
  {
    delay(1);
    if( Serial.available() > 0 )
    {
      char c = Serial.read();  //gets one byte from serial buffer
      if (c == ';')
      {
        goto parce;
      }
      readStr += c;
    } //makes the string readString
  }     
  parce:  
  if ( readStr.length() > 0 )
  {
    pos = readStr.length(); //capture string length
    str1 = readStr.substring(0, readStr.indexOf(' ')); //first part of string
    str2 = readStr.substring(readStr.indexOf(' ') + 1, pos);
    Serial.println("Recieving command: " + str1 + str2);
    command(str1, str2);
    readStr = "";
  }
}

void command(String str1, String str2)
{
  String str = str1 + str2;
  if( str == "G01")
  {
    Serial.print("hello world");
  }
  else if( str1 == "X")
  {
    int num = 0;
    int n = str2.length();
    for( int i = 0; i < n; i++)
    {
      num += (str2[i] - 48) * pow(10,n-i-1);//在百位數以上的時候,會有少1的bug
      //
      //Serial.print("num = ");
      //Serial.println(num);
    }
    //Serial.print("n = ");
    //Serial.println(n);
    if( n > 2)//修正bug用的...
    {
      num += 1;
    }
    Serial.println(num);
    //motro rotate
    //
  }
  else
  {
    Serial.println("Incorrect input");
  }
}