let inpt = readLine()!

let hourMin = inpt.split(separator: ":").map{Int($0)!}

var h:Int = hourMin[0]
var m:Int = hourMin[1]

m+=5

while m>=60 {
    m-=60
    h+=1
}
h = h % 24

var ans = ""
if(h<10) {
    ans+="0"
}
ans += (String(h) + ":")
if(m<10) {
    ans+="0"
}
ans += String(m)
print(ans)