NEED TO FIX MILLIS FUNCTION ON LCD SCREEN

Hello I need to fix value on LCD ,when is int b over 60 value (i mean seconds) I get value 19 istead 01 on display . I need get value 01.How to fix it please.
Thank you

Program:

#include <LiquidCrystal.h>

LiquidCrystal lcd(12,11,5,4,3,2);

int x = 0;

void setup() {
  lcd.begin(16,4);
  Serial.begin(9600);

}

void loop() {
 if(Serial.available() > 0){ int r =0;
int z =Serial.read();
r = 12%13;

Serial.println(r);
lcd.print(r);
 }

int a = millis()%1000;
int b =millis()%60000/1000;
Serial.print(a);
Serial.print("---");
Serial.println(millis()/60000);
lcd.setCursor(1,1);
lcd.print(millis()/60000);
lcd.print("min");

lcd.print(b);

}

  }
r = 12%13;

Why? That is a constant, with a value of 12.

If printing 0 after printing 59 results in 09 appearing, then print a space after printing b, every time. "59 " will be replaced by "0 ", and the space from the first print statement won't be overwritten, but, so what?

sait_cz: when is int b over 60 value (i mean seconds) I get value 19 istead 01 on display . I need get value 01

I don't understand.

Give some examples of values in millis() and the associated values you want to see on the display.

...R

Exactly what sequence to do get and what sequence do you want ?