I am not sure how to use Serial.println [closed] - c++

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I wrote the code below. But Serial.println occurred errors.
I believe in the code is wrong. But I don't know what is wrong.
Could you tell me how to fix the issue?
class Move {
public:
int x;
int y;
void go(int w, int h);
};
void Move::go(int w, int h) {
x += w;
y += h;
}
Move m;
void setup() {
Serial.begin(9600);
m.x = 10;
m.y = 20;
Serial.println("at start: x is %d, y is %d", m.x, m.y);
}
void loop() {
m.go(10, 20);
Serial.println("x is %d, y is %d", m.x, m.y);
}
The error is below:
c:\Users\a\Dropbox\!Arduino\class\classes.ino: In function 'void setup()':
classes:19:58: error: no matching function for call to 'HardwareSerial::println(const char [27], int&, int&)'
Serial.println("at start: x is %d, y is %d", m.x, m.y);
^
In file included from C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Stream.h:26:0,
from C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/HardwareSerial.h:29,
from C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Arduino.h:233,
from sketch\classes.ino.cpp:1:
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:77:12: note: candidate: size_t Print::println(const __FlashStringHelper*)
size_t println(const __FlashStringHelper *);
^~~~~~~
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:77:12: note: candidate expects 1 argument, 3 provided
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:78:12: note: candidate: size_t Print::println(const String&)
size_t println(const String &s);
^~~~~~~
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:78:12: note: candidate expects 1 argument, 3 provided
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:79:12: note: candidate: size_t Print::println(const char*)
size_t println(const char[]);
^~~~~~~
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:79:12: note: candidate expects 1 argument, 3 provided
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:80:12: note: candidate: size_t Print::println(char)
size_t println(char);
^~~~~~~
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:80:12: note: candidate expects 1 argument, 3 provided
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:81:12: note: candidate: size_t Print::println(unsigned char, int)
size_t println(unsigned char, int = DEC);
^~~~~~~
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:81:12: note: candidate expects 2 arguments, 3 provided
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:82:12: note: candidate: size_t Print::println(int, int)
size_t println(int, int = DEC);
^~~~~~~
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:82:12: note: candidate expects 2 arguments, 3 provided
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:83:12: note: candidate: size_t Print::println(unsigned int, int)
size_t println(unsigned int, int = DEC);
^~~~~~~
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:83:12: note: candidate expects 2 arguments, 3 provided
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:84:12: note: candidate: size_t Print::println(long int, int)
size_t println(long, int = DEC);
^~~~~~~
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:84:12: note: candidate expects 2 arguments, 3 provided
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:85:12: note: candidate: size_t Print::println(long unsigned int, int)
size_t println(unsigned long, int = DEC);
^~~~~~~
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:85:12: note: candidate expects 2 arguments, 3 provided
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:86:12: note: candidate: size_t Print::println(double, int)
size_t println(double, int = 2);
^~~~~~~
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:86:12: note: candidate expects 2 arguments, 3 provided
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:87:12: note: candidate: size_t Print::println(const Printable&)
size_t println(const Printable&);
^~~~~~~
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:87:12: note: candidate expects 1 argument, 3 provided
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:88:12: note: candidate: size_t Print::println()
size_t println(void);
^~~~~~~
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:88:12: note: candidate expects 0 arguments, 3 provided
c:\Users\a\Dropbox\!Arduino\class\classes.ino: In function 'void loop()':
classes:24:48: error: no matching function for call to 'HardwareSerial::println(const char [17], int&, int&)'
Serial.println("x is %d, y is %d", m.x, m.y);
^
In file included from C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Stream.h:26:0,
from C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/HardwareSerial.h:29,
from C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Arduino.h:233,
from sketch\classes.ino.cpp:1:
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:77:12: note: candidate: size_t Print::println(const __FlashStringHelper*)
size_t println(const __FlashStringHelper *);
^~~~~~~
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:77:12: note: candidate expects 1 argument, 3 provided
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:78:12: note: candidate: size_t Print::println(const String&)
size_t println(const String &s);
^~~~~~~
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:78:12: note: candidate expects 1 argument, 3 provided
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:79:12: note: candidate: size_t Print::println(const char*)
size_t println(const char[]);
^~~~~~~
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:79:12: note: candidate expects 1 argument, 3 provided
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:80:12: note: candidate: size_t Print::println(char)
size_t println(char);
^~~~~~~
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:80:12: note: candidate expects 1 argument, 3 provided
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:81:12: note: candidate: size_t Print::println(unsigned char, int)
size_t println(unsigned char, int = DEC);
^~~~~~~
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:81:12: note: candidate expects 2 arguments, 3 provided
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:82:12: note: candidate: size_t Print::println(int, int)
size_t println(int, int = DEC);
^~~~~~~
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:82:12: note: candidate expects 2 arguments, 3 provided
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:83:12: note: candidate: size_t Print::println(unsigned int, int)
size_t println(unsigned int, int = DEC);
^~~~~~~
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:83:12: note: candidate expects 2 arguments, 3 provided
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:84:12: note: candidate: size_t Print::println(long int, int)
size_t println(long, int = DEC);
^~~~~~~
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:84:12: note: candidate expects 2 arguments, 3 provided
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:85:12: note: candidate: size_t Print::println(long unsigned int, int)
size_t println(unsigned long, int = DEC);
^~~~~~~
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:85:12: note: candidate expects 2 arguments, 3 provided
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:86:12: note: candidate: size_t Print::println(double, int)
size_t println(double, int = 2);
^~~~~~~
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:86:12: note: candidate expects 2 arguments, 3 provided
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:87:12: note: candidate: size_t Print::println(const Printable&)
size_t println(const Printable&);
^~~~~~~
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:87:12: note: candidate expects 1 argument, 3 provided
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:88:12: note: candidate: size_t Print::println()
size_t println(void);
^~~~~~~
Please tell me what is wrong with me.

Answer 1

The problem is that you are using Serial.println() as if it where printf(). Serial.println(), as specified in the documentation, takes only two arguments, the first being the value that you want to print through the serial port, and the second being the format that you want that value to be sent as.
What you need to do to achieve what you originaly wanted is first concatenate the values that you want to send over and then send them with Serial.println().

Answer 2

If you want to print four things, most often the fastest and most efficient way is to simply call print 4 times. Print is pretty lightweight compared to involving format strings. If you're writing for a PC who cares. But if you're writing for a ATTINY or an UNO or something then you can usually use the savings.
Serial.println("at start: x is %d, y is %d", m.x, m.y);
becomes:
Serial.print("at start: x is ");
Serial.print(m.x);
Serial.print(", y is ");
Serial.println(m.y);
Note that I'm using print on all but the last one. Only the last one is println. That way only the last one gives a line break and the receiver doesn't have any way to know if I sent with one statement or three. It all goes in the same buffer and comes out the same way.