Auto comment: topic has been updated by ryuga222 (previous revision, new revision, compare).

First of all notice that this is an old problem. So your execution time will be multiplied by 2.

There are many optimizations that you can do —

1. Honestly use scanf/printf for IO.
2. You are using too much long long variables, it takes too much time. Use only when necessary.
3. You are using long long BLOCK = 512, if you use const long long compiler will optimize division / modulo for with the number.
4. In the compare function, you are calculating the block number there, again and again. The division is a costly operator. You can pre-calculate the block number in main function and just use that.
5. You are accessing the cnt[] array 5 times in add/remove function. But it is possible to design those by accessing only twice or even once.
6. Silly optimization — if anywhere you have i++, and changing it to ++i doesn't affect much. Then use ++i. Somehow ++i is more faster.

So, it is reasonable that you got TLE.