const arr = [
{ start: '01:00', end: '04:00' },
{ start: '05:00', end: '08:00' },
{ start: '07:00', end: '11:00' },
{ start: '09:30', end: '18:00' },
];
const overlapping = (a, b) => {
const getMinutes = s => {
const p = s.split(':').map(Number);
return p[0] * 60 + p[1];
};
return getMinutes(a.end) > getMinutes(b.start) && getMinutes(b.end) > getMinutes(a.start);
};
const isOverlapping = (arr) => {
let i, j;
for (i = 0; i < arr.length - 1; i++) {
for (j = i + 1; j < arr.length; j++) {
if (overlapping(arr[i], arr[j])) {
return true;
}
};
};
return false;
};
console.log(isOverlapping(arr));