(function() {
    'use strict';

    var fs = require('fs');
    var contents = fs.readFileSync('/dev/stdin', 'utf-8');

    var watch = function(n) {
        var h = Math.floor(n / 3600);
        var m = Math.floor((n - 3600 * h) / 60);
        var s = n % 60;
        return h + ":" + m + ":" + s;
    }

    console.log(watch(parseInt(contents)));
})();