C++ code string substring

Question

*/this code for serial domin
AHMED ABDULSADA ALSARAEE

void setup() {
// Open serial communications and wait for port to open:
Serial.begin(9600);
while (!Serial) {
; // wait for serial port to connect. Needed for native USB port only
}

// send an intro:
Serial.println("\n\nString substring():");
Serial.println

Answer 1

println is not predefined in or c/ c++