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/*
  String charAt() and setCharAt()

  Examples of how to get and set characters of a String

  created 27 Jul 2010
  modified 2 Apr 2012
  by Tom Igoe

  This example code is in the public domain.

  https://www.arduino.cc/en/Tutorial/BuiltInExamples/StringCharacters
*/
 

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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
  }

  Serial.println("\n\nString charAt() and setCharAt():");
}
 

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void loop() {
  // make a String to report a sensor reading:
  String reportString = "SensorReading: 456";
  Serial.println(reportString);

  // the reading's most significant digit is at position 15 in the reportString:
  char mostSignificantDigit = reportString.charAt(15);

  String message = "Most significant digit of the sensor reading is: ";
  Serial.println(message + mostSignificantDigit);

  // add blank space:
  Serial.println();

  // you can also set the character of a String. Change the : to a = character
  reportString.setCharAt(13, '=');
  Serial.println(reportString);

  // do nothing while true:
  while (true);
}