Here are the main categories of greedy problems you have practiced:
Sorting-based:: Two City Scheduling, Activity Selection. Sort by some criterion, then select greedily.
Heap-based:: Connect Sticks, Task Scheduler. Use a heap to always pick the best available option.
Two-pointer:: Bag of Tokens, Assign Cookies. Process from both ends to maximize.
Range tracking:: Valid Parenthesis String. Track min and max possible values.
Reverse thinking:: Broken Calculator. Work backwards when forward is complex. Recognizing these patterns speeds up problem-solving significantly.