Intervals - Non-overlapping Intervals (Max Non-Overlap)
The following code attempts to find the maximum number of non-overlapping intervals. Which line contains a subtle bug that causes incorrect results on some inputs?
```python
intervals.sort(key=lambda x: x[0])
removals = 0
last_end = intervals[0][1]
for i in range(1, len(intervals)):
if intervals[i][0] < last_end:
removals += 1
last_end = min(last_end, intervals[i][1])
else:
last_end = intervals[i][1]
return len(intervals) - removals
```