gistfile1.js

var data = { truck: { trips: [ { begin: 100, end: 500 }, { begin: 700, end: 1000 }, { begin: 1100, end: 1200 }, { begin: 1300, end: 2000 } ] } };

function validate(array, input) {
    for (var i = 0; i < array.truck.trips.length; i++) {
        var trip = array.truck.trips[i];
        if (input.begin >= trip.begin && input.begin <= trip.end) {
            // console.log('invalid beginning');
            return false;
        } else if(input.end >= trip.begin && input.end <= trip.end) {
            // console.log('invalid end');
            return false;
        }
    };
    return true;
}

console.log('501 699 should be true: ', validate(data, {begin:501, end:699}));
console.log('501 701 should be false:', validate(data, {begin:501, end:701}));
console.log('499 699 should be false:', validate(data, {begin:499, end:699}));
console.log('499 701 should be false:', validate(data, {begin:499, end:701}));