//char -128_127
//int -32768_32767
//long -20亿_20亿

void setup() {
  Serial.begin(9600);
  
  // put your setup code here, to run once:
  char charnum = 127 +1;
  unsigned char num = 127 +1;
  Serial.println(charnum,DEC);
  Serial.println(num,DEC);

  long second = 0;
  second = 24*60*60L;
  Serial.println(second);
  
  M(2);
  M(0);

  Stringoutput();//用指针输出字符串


  delay(3000);
}

void loop() {
  // put your main code here, to run repeatedly:M();

}

int M(int isUpper)
{
  byte i = 0;
  if(isUpper)
  i = 65;
  else
  i = 97;
  byte num = i + 26;
  for(i;i<num;i++)
  {
    Serial.print(char(i));
    Serial.println(i);
  }
  return 0;
}

void Stringoutput()
{
  char* str = "Hello word";

  Serial.println(str);
  Serial.print("sizeof(str)==");
  Serial.println(sizeof(str));

}