CompressInterval = (intervals) => {
const output = [];
let prev = [...intervals[0]];
for (let i = 1; i < intervals.length; i++) {
const cur = [...intervals[i]];
if(cur[0] < prev[1]) {
if(cur[1] > prev[1]) prev[1] = cur[1];
} else {
output.push(prev);
prev = cur;
}
}
output.push(prev);
return output;
}