#include <Keypad.h>
const byte ROWS = 4; 
const byte COLS = 4; 

char hexaKeys[ROWS][COLS] = {
  {'1', '2', '3', 'A'},
  {'4', '5', '6', 'B'},
  {'7', '8', '9', 'C'},
  {'*', '0', '#', 'D'}
};

byte rowPins[ROWS] = {9, 8, 7, 6}; 
byte colPins[COLS] = {5, 4, 3, 2}; 

Keypad customKeypad = Keypad(makeKeymap(hexaKeys), rowPins, colPins, ROWS, COLS); 

void setup(){
  Serial.begin(9600);
}
  
void loop(){
  delay(1000);
  Serial.flush();
  Serial.println("enter a value for table - ");
  
  char customKey = customKeypad.getKey();
    
 if(customKey) // get the display on serial monitor
 {

   Serial.println(customKey);
   Serial.println("--------");
   int k=customKey-'0';
   for(int i=1;i<=10;i++)
   {
    Serial.print(k);
    Serial.print("x");
    Serial.print(i);
    Serial.print("=");
    Serial.println(i*k);
   }
   delay(3000);
   
   
 }
 

}