# 09.12.2025
[3583. Count Special Triplets](https://leetcode.com/problems/count-special-triplets/description) medium
Count a[i]==a[j]*2==a[k] #medium #prefix_sum
[3583. Count Special Triplets](https://leetcode.com/problems/count-special-triplets/description) medium
Count a[i]==a[j]*2==a[k] #medium #prefix_sum
👍1
# 10.12.2025
[3577. Count the Number of Computer Unlocking Permutations](https://leetcode.com/problems/count-the-number-of-computer-unlocking-permutations/) medium
Permutations to unlock all c[j] right and bigger than c[i] #medium #combinatorics
[3577. Count the Number of Computer Unlocking Permutations](https://leetcode.com/problems/count-the-number-of-computer-unlocking-permutations/) medium
Permutations to unlock all c[j] right and bigger than c[i] #medium #combinatorics
👍1
# 11.12.2025
[3531. Count Covered Buildings](https://leetcode.com/problems/count-covered-buildings/description/) medium
Count surrounded dots on XY plane #medium
[3531. Count Covered Buildings](https://leetcode.com/problems/count-covered-buildings/description/) medium
Count surrounded dots on XY plane #medium
👍1