fn true_main() {
  use std::io::{BufRead, BufWriter, Write};
  let stdin = std::io::stdin();
  let stdout = std::io::stdout();
  let mut stdin = stdin.lock().lines();
  let mut stdout = BufWriter::new(stdout.lock());

  #[allow(unused_macros)]
  macro_rules! input {
    ($x: ident) => {
      $x = stdin.next().unwrap().unwrap().parse().unwrap();
    };
    ($x: ident: $t: ty) => {
      let $x: $t;
      $x = stdin.next().unwrap().unwrap().parse().unwrap();
    };
    ($($x: ident), +) => {
      let s = stdin.next().unwrap().unwrap();
      let mut it = s.split_whitespace();
      $($x = it.next().unwrap().parse().unwrap();)+
    };
    ($($x: ident: $t:ty), +) => {
      $(let $x: $t;)+
      let s = stdin.next().unwrap().unwrap();
      let mut it = s.split_whitespace();
      $($x = it.next().unwrap().parse().unwrap();)+
    };
  } 

  #[allow(unused_macros)]
  macro_rules! input_n {
    ($x: ident) => {
      $x = stdin.next().unwrap().unwrap().split_whitespace().map(|x| x.parse().unwrap()).collect();
    };
    ($x: ident: $t: ty) => {
      let $x: $t;
      $x = stdin.next().unwrap().unwrap().split_whitespace().map(|x| x.parse().unwrap()).collect();
    };
  }

  #[allow(unused_macros)]
  macro_rules! output {
    ($fmt: expr) => (write!(stdout, $fmt).unwrap());
    ($fmt: expr, $($arg: tt)*) => (write!(stdout, $fmt, $($arg)*).unwrap());
  }

  #[allow(unused_macros)]
  macro_rules! outputln {
    ($fmt: expr) => (writeln!(stdout, $fmt).unwrap());
    ($fmt: expr, $($arg: tt)*) => (writeln!(stdout, $fmt, $($arg)*).unwrap());
  }



  input!(a: i32, b: i32, s: String);
  let y: f64 = s[3..].parse().unwrap();
  let x = (a + 48) * 60 + b;
  let x = x + ((y * 60.0 + y.signum() * 1e-12) as i32) - 9 * 60;

  outputln!("{:02}:{:02}", x / 60 % 24, x % 60);
}

fn main() {
  let builder = std::thread::Builder::new().stack_size(64 * 1024 * 1024);
  let handler = builder.spawn(true_main).unwrap();
  handler.join().unwrap();
}