time+15(1)

function time15 (input)
{
    let chas = Number(input.shift());
    let minuti = Number(input.shift());
    if ( minuti <= 44)
    {
        let minuti15= minuti +15;
        console.log(`${chas}:${minuti15}`)
    }
    else{
    let chasmin= chas*60;
    let obshtomin = chasmin+ minuti+15;
    novchas = Math.floor(obshtomin/60);
    novmin = (obshtomin % 60 );
    if (novmin<10)
    {
        if (novchas>=24){
        novchas = 0
        }


        console.log(`${novchas}:0${novmin}`)
    }
    else{
        if (novchas>=24){
            novchas = 0
            }
    console.log(`${novchas}:${novmin}`);
    }
    }

}