def main():
    t=input()
    h=int(t[0:2])
    m=int(t[3:5])
    m+=5
    if m>=60:
        m-=60
        h+=1
    if h>=24:
        h-=24
    print(f"{str(h).zfill(2)}:{str(m).zfill(2)}")
    pass


if __name__ == "__main__":
    main()