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Remove duplicates in-place from an ascending integer array and return the number of unique values. The retained prefix must preserve ascending order.
{1, 1, 2, 2, 4}, 5length 3: {1, 2, 4}Write down the input contract and the failure cases before coding.
Ready to run the file open above against 1 test.
Because the input is sorted, a value is new precisely when it differs from the last retained value. The read index visits every original item while write marks the next free position in the valid prefix, giving linear time and constant extra space.
your-solution.c.solution.c only after a real attempt.This intermediate C exercise focuses on Read/write indices, In-place algorithms, Array contracts. Its requirements define the exact behavior to implement before you write code.
Start with the displayed example input and expected output, then test a boundary case suggested by the requirements. Open your-solution.c and select Run code. The browser uses the same safe C subset as the C course, including a test harness for exercise functions.
Attempt Deduplicate a sorted integer array first. Then open the read-only solution file to compare the contract, edge-case handling, and implementation choices—not simply to copy the final code.