Convert a string so that every alternate character is uppercase, starting with the first character as uppercase. Non-alp...
The 3's Game
EasyFor every number from 1 to N, print "Three" if divisible by 3 (but not 9), "DoubleThree" if divisible by 9, or the numbe...
Flip & Sum
EasyReverse the digits of two numbers, add the reversed numbers together, then reverse the digits of the sum to get the fina...
Even-Odd Sort
MediumSort an array where even numbers are sorted in ascending order and odd numbers are sorted in descending order, while mai...
Character Distance
EasyFind the distance between the first and last occurrence of a given character in a string. Distance is the number of posi...
Snake Matrix Path
MediumGiven an m×n matrix, print its elements in a zigzag "snake" pattern. Start from top-left, go right in first row, then le...
Disappearing Pairs
MediumRemove adjacent pairs of the same character from a string repeatedly until no such pairs remain. Process from left to ri...
Minimal Merge Array
MediumGiven two sorted arrays, merge them into one sorted array. Count and return the minimum number of comparisons needed dur...
Power of String
EasyA string's "power" is defined as the length of the longest run of identical consecutive characters. Find the maximum pow...
Circular Queue Rotation
MediumSimulate a circular queue rotation k times. After each rotation, the front element moves to the back. Report the front e...