#include<stdio.h>

int main()
  {
    int time = 0;
    int sec = 0;
    
    scanf("%d%d",&time,&sec);
    sec = sec + 5;
    
    switch (sec)
      {
        case 64:
          sec = 4;
          break;
        case 63:
          sec = 3;
          break;
        case 62:
          sec = 2;
          break;
        case 61:
          sec = 1;
          break;
        case 60:
          sec = 0;
        default:
          break;
      }
    if(time == 23)
      {
        time =0;
      }
    else if(sec > 59)
      {
        time++;
      }
    printf("%02d:%02d\n", time,sec);
  return 0;
}